A mortar automatic proportioning and stable mixing control method based on online water content detection

Abstract

This invention discloses an automatic mortar proportioning and stabilization mixing control method based on online moisture content detection, relating to the field of mortar production and proportioning control technology. The method first performs online moisture content detection on the wet sand entering the mixing system. Based on the real-time moisture content data, the wet sand feed amount is converted into an absolute dry sand baseline amount, and the target total water consumption, the initial planned water addition, and the reserved correction water amount are determined in conjunction with a preset mortar masterbatch formula. Then, the first water addition and mixing are performed. During the initial discharge stage, the state parameters of the first wave of material are collected within a preset first-wave material verification window and compared with a preset target range. When the state parameters of the first wave of material are lower than the preset target range, a limited secondary water addition is performed, and mixing continues until the stabilization endpoint is reached, at which point the finished mortar is output. This invention can improve the mortar proportioning accuracy, discharge continuity, and batch consistency under fluctuating wet sand conditions.

Description

Technical Field

[0001] This invention relates to the field of mortar production, specifically to a method for automatic proportioning and stable mixing control of mortar based on online moisture content detection. Background Technology

[0002] In current mortar production processes, especially on production lines where wet sand is directly used in batching and mixing, the moisture content of the sand itself directly affects the total amount of water entering the system. Because wet sand is easily affected by environmental temperature and humidity, spraying conditions, differences in surface and inner layer moisture content, and the stability of different batches of sand during stockpiling, transportation, and loading, its actual moisture content often fluctuates dynamically. When a fixed method of adding wet sand and water is used in the production process, the actual effective water content of different batches of mortar under the same formula can be inconsistent, leading to fluctuations in the mortar's flowability, discharge continuity, wetness, and workability after mixing. Some batches may exhibit issues such as excessively dry material, localized clumping, intermittent discharge, and difficulty in spreading, while other batches may show excessively wet material, a shiny surface, excessively thick slurry, or decreased subsequent stability, ultimately affecting the continuity of mortar production and the consistency of finished product quality.

[0003] Furthermore, existing production methods rely heavily on empirical estimations, single sampling inspections, or compensation based on fixed empirical values ​​to determine the moisture content of wet sand, making it difficult to accurately reflect the actual moisture content of the wet sand entering the mixing system. Even if a moisture content test is conducted before batching, discrepancies between the test location and the actual material discharge state, or the presence of localized high-humidity areas, dry areas, or short-term uneven mixing within the silo, can still lead to deviations between the calculated water addition and the actual mixing state. This is particularly problematic in systems like mortar, which are highly sensitive to working conditions. Even if the material formed after the first round of mixing is generally close to the target state, significant differences may still occur in the initial discharge stage due to insufficient free water, inadequate slurry film formation, or uneven aggregate surface coating. This inconsistency between batches increases the risk of subsequent construction fluctuations and rework.

[0004] Furthermore, mortar does not simply reach a stable output after a set time during mixing. The motor load, flow expansion capacity, discharge continuity, and internal uniformity of the material will all change under different moisture contents. If the entire batch is discharged directly after the first round of mixing, it is easy to discharge material that is not fully homogenized or deviates from the target state. If a large amount of water is added after deviations are discovered, it may cause local water accumulation, excessively long re-homogenization time, and disruption of the entire batch cycle. Therefore, under the condition of fluctuating moisture content of wet sand, how to promptly verify the state of the first batch of material after the first round of mixing based on the front-end proportioning calculation, and implement controlled water addition and continued mixing when necessary, so that the entire batch of mortar finally reaches a stable and consistent discharge state, has become a long-standing problem in the automated mortar production process, and it is difficult to balance efficiency and stability.

[0005] In view of the above problems, a method for automatic mortar proportioning and stable mixing control based on online moisture content detection is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide an automatic mortar proportioning and stable mixing control method based on online moisture content detection, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for automatic proportioning and stable mixing control of mortar based on online moisture content detection, comprising the following steps: S1. Perform online moisture content detection on the wet sand entering the mixing system to obtain real-time moisture content data of the wet sand; S2. Based on the real-time moisture content data of the wet sand, the amount of wet sand fed is converted into the baseline amount of absolutely dry sand, and the target total water consumption is determined in combination with the preset mortar masterbatch formula. The first round of planned water addition and reserved correction water volume are further calculated. S3. Add water for the first time according to the planned water addition amount, and mix the converted wet sand with the remaining materials in the mortar masterbatch formula for the first time; S4. Collect the state parameters of the first wave of material in the preset first wave material verification window at the beginning of the discharge stage, and compare the state parameters of the first wave of material with the preset target range. S5. When the state parameters of the first wave of material are lower than the preset target range, a limited secondary water replenishment is performed on the mixing system, and mixing continues after the secondary water replenishment; S6. During the continued mixing process, the mortar state is judged to be stable at the endpoint, and the finished mortar is output when the preset stable endpoint is reached.

[0008] Preferably, the mortar masterbatch formula includes cementitious materials, fine aggregates, water-retaining and thickening components, auxiliary anti-skid components, and interface modifying components. The cementitious materials include at least cement and one or more mineral admixtures. The fine aggregates are the amount of oven-dry sand converted from wet sand. The water-retaining and thickening components include at least cellulose ethers. The auxiliary anti-skid components include at least starch ethers. The interface modifying components include at least redispersible latex powder.

[0009] Preferably, the mortar masterbatch formula, based on an oven-dry datum, comprises the following components in parts by weight: 78-82 parts fine aggregate, 11-14 parts cement, 2-4 parts limestone powder, 1-3 parts fly ash, 0.5-1.2 parts hydrated lime, 0.14-0.20 parts cellulose ether, 0.015-0.035 parts starch ether, and 0.20-0.45 parts redispersible latex powder.

[0010] Preferably, the wet sand is manufactured sand or a mixture of river sand and manufactured sand, and the wet sand meets at least some of the following conditions: fineness modulus is 2.5 to 2.9, stone powder content is 4.0% to 7.5%, mud content is not higher than 1.2%, and the working range of online detection moisture content is 3.0% to 8.5%.

[0011] Preferably, the initial planned water addition and the reserved correction water addition in step S2 are determined based on the difference between the target total water consumption and the water brought in by the wet sand, wherein the water brought in by the wet sand is calculated based on the real-time moisture content data of the wet sand and the amount of wet sand fed. Let the baseline quantity of absolutely dry sand be The real-time moisture content of the wet sand is W, where W is the mass fraction based on the total mass of the wet sand, and the target total water consumption is... , The actual amount of wet sand fed for: ; Water carried in by wet sand for: ; Theoretical total additional water for: ; First round of planned water addition for: ; Reserved correction water volume for: ; in, This is the coefficient for the first round of water addition, and .

[0012] Preferably, the planned water addition in step S3 is... Theoretical total additional water 82%–90% of the water volume is reserved for correction. Theoretical total additional water 10% to 18%.

[0013] Preferably, the preset first wave material verification window in step S4 is a preset time interval or a preset discharge volume interval after the start of discharge, and the actual secondary water replenishment volume in step S5 is not higher than the reserved correction water volume. The preferred total water consumption is... 2% to 4%.

[0014] Preferably, the first wave material status parameters in step S4 include one or more of the following: discharge end humidity value, stirring motor current fluctuation value, stirring torque change value, first wave material flow expansion value, and discharge continuity parameters.

[0015] Preferably, in step S5, secondary water replenishment is performed only when the state parameters of the first wave of material are lower than the preset target range, and stirring continues after secondary water replenishment; when the state parameters of the first wave of material are within the preset target range, secondary water replenishment is not performed and stirring continues directly until the preset stable endpoint is reached.

[0016] Preferably, the stabilization endpoint in step S6 is determined by at least one of the following methods: when the current fluctuation of the mixing motor is lower than a preset threshold within a continuous preset time period, and / or the humidity signal in the mixer is within a preset target range, and / or the discharge continuity parameter reaches the set standard, the mortar is determined to have reached the stabilization endpoint.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention combines online moisture content detection of wet sand, conversion of dry sand benchmark, first round of planned water addition, verification of the state of the first batch of material, limited secondary water replenishment, and determination of the stable quality endpoint. In the mortar production process, the proportion calculation and the first water addition and mixing are completed based on the actual moisture content of the wet sand. Then, at the initial stage of discharge, the wetness, flow state, and discharge continuity of the first batch of material are verified. If the material is too dry or has not reached the target state, controlled water replenishment and continued mixing are implemented. This ensures that each batch of mortar can maintain a relatively consistent effective water content, slurry film formation state, and discharge stability before entering the use station. It reduces the problems of material dryness, local clumping, intermittent discharge, unstable flowability, and batch-to-batch quality differences caused by fluctuations in the moisture content of wet sand. It improves the continuity, controllability, and consistency of finished products in automated mortar production and solves the problems of inaccurate actual mortar proportions, unstable state after mixing, and poor consistency of discharge quality under the condition of fluctuating moisture content of wet sand in the prior art. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention provides a technical solution: a method for automatic proportioning and stable mixing control of mortar based on online moisture content detection, comprising the following steps: S1. Perform online moisture content detection on the wet sand entering the mixing system to obtain real-time moisture content data of the wet sand; S2. Based on the real-time moisture content data of wet sand, the amount of wet sand fed is converted into the baseline amount of absolutely dry sand, and the target total water consumption is determined in combination with the preset mortar masterbatch formula. The first round of planned water addition and reserved correction water volume are further calculated. S3. Add water for the first time according to the planned water volume, and mix the converted wet sand with the remaining materials in the mortar masterbatch formula for the first time; S4. Collect the state parameters of the first wave of material in the preset first wave material verification window at the beginning of the discharge stage, and compare the state parameters of the first wave of material with the preset target range. S5. When the state parameters of the first batch of material are lower than the preset target range, a limited secondary water replenishment is performed on the mixing system, and mixing continues after the secondary water replenishment; S6. During the continued mixing process, the mortar state is judged at the stable end point, and the finished mortar is output when the preset stable end point is reached.

[0020] An automatic mortar proportioning and stable mixing control method based on online moisture content detection is implemented on a production line in conjunction with a wet sand silo, sampling and testing components, powder metering components, a main mixer, a primary water supply component, a secondary water replenishment component, a discharge section, and a control component. A sampling tube is horizontally installed on the side wall of the wet sand silo near the discharge port, communicating with the interior of the silo. The axis of the sampling tube is preferably perpendicular to the natural descent direction of the wet sand within the silo to reduce sampling deviation caused by continuous impact from above during testing. A reciprocating sampling rod is installed inside the sampling tube, with a sampling cavity formed at the front end. When the sampling rod is pushed inward, the sampling cavity extends into the wet sand flow area, allowing the current batch of wet sand to enter the sampling cavity. After the sampling rod is pulled outward, the sampling cavity enters the testing station at the outer end of the sampling tube. A microwave moisture content detection unit is installed at the testing station to read the moisture content of the wet sand in the sampling cavity. The microwave moisture content detection unit emits a microwave signal that passes through the sand sample in the sampling chamber. It calculates the current moisture content of the wet sand by utilizing the difference in microwave energy attenuation and phase change caused by moisture in the wet sand. After the detection is completed, the sampling rod returns to its original position, and the detected sand sample is returned to the wet sand silo or fed into the recovery hopper to complete one detection cycle. Sampling is preferably performed once before each batch of materials is prepared. In continuous production, it is preferably performed every 20 to 60 seconds. Alternatively, it can be performed again after the cumulative discharge from the wet sand silo reaches a preset value to ensure that the wet sand entering the mixing system always corresponds to the moisture content data of the current time period.

[0021] After receiving the real-time moisture content data of the wet sand, the control component first calculates the actual amount of wet sand to be added in this batch by using the baseline amount of oven-dried sand as the target value. Then, combined with the preset mass of the powder component in the mortar masterbatch formula and the target total water consumption, it calculates the planned water addition for the first round and the reserved correction water amount for this batch. After being metered, the wet sand, along with cement, mineral admixtures, and functional components, enters the main mixer. The main mixer is preferably a horizontal shaft paddle mixer or a forced mixer. The first water addition is preferably initiated within 2 to 8 seconds after the material enters the machine, allowing the dry powder and wet sand to form a basic wetting layer. After the first round of planned water addition, the first mixing stage begins. This first mixing stage preferably includes a pre-wetting and mixing stage and a post-homogenization and dispersion stage. The pre-wetting and mixing stage lasts 15 to 30 seconds, with the mixing speed controlled at 50% to 70% of the rated speed, ensuring that the powder adheres evenly to the outer surface of the wet sand particles and forms an initial slurry film. The post-homogenization and dispersion stage lasts 20 to 45 seconds, with the mixing speed controlled at 75% to 100% of the rated speed, used to break up local clumps, eliminate unwetted dry cores, and establish the continuity of the overall slurry. After the first mixing, the material is ready for discharge, but at this point, it is not immediately determined that the entire batch of mortar has reached the target quality; instead, the first wave of material verification begins.

[0022] The initial material verification phase begins at the start of discharge, and the control component collects data on the status of the initial material within a preset verification window. This verification window is preferably 3 to 12 seconds after the start of discharge, but can also be set to the first 5% to 15% of the total discharge volume. Within this window, a status acquisition unit is installed near the discharge port to detect the status parameters of the initial material. These parameters include at least one or more of the following: discharge continuity, initial material wetness, motor load changes, and flow state. The continuity of material discharge can be determined by the image recognition module or the weight change rate module at the discharge port. When the first wave of material falls intermittently, hangs on the wall for a short time, or has obvious dry particles exposed, it is determined that the current batch has a tendency to be insufficient in free water. The change in motor load can be obtained by reading the current or torque signal of the stirring motor. When the current fluctuation is continuously higher than the preset range from the end of the first stirring to the first wave of material window, it indicates that the internal resistance of the material is too large and the degree of wetting is insufficient. The degree of wetting of the first wave of material can be verified by a near-field microwave probe, capacitive probe, or short-range sampling and retesting module at the discharge end. The flow state can be determined by parameters such as the material unfolding length, the continuous length of the material strip, and the stability of the material flow cross section. The control component compares the collected state parameters of the first wave of material with the preset target range. Only when the state parameters of the first wave of material indicate that the current batch is still short of water or has not reached the target wetting state will the secondary water replenishment process be initiated.

[0023] Secondary water replenishment is achieved through a water injection assembly positioned above or to the side of the main mixer. This assembly is preferably composed of multi-point atomizing nozzles or fan-shaped nozzles, spaced along the length of the mixer to ensure rapid water coverage of the main mixing area without localized water accumulation. The amount of secondary water replenishment is controlled by the control assembly based on a pre-set correction volume. The replenishment process is preferably completed within 2 to 8 seconds, immediately followed by the continued mixing phase. This continued mixing phase preferably lasts 10 to 35 seconds. During this phase, the replenished water is redistributed throughout the slurry under high-speed tumbling, correcting any localized dryness caused by fluctuations in the wet sand. During continued mixing, the control assembly simultaneously reads one or more of the following signals: the mixer motor current signal, the mixer internal humidity signal, and the discharge continuity signal. When the current fluctuation amplitude decreases and stabilizes within a preset duration, or the internal humidity signal enters the target range and its rate of change decreases, or the discharge continuity changes from intermittent to stable and continuous, the material is deemed to have reached its stable quality endpoint. Once the stable quality endpoint is reached, the control components issue a finished product release command, and the entire batch of mortar enters the subsequent discharge and use processes. Through this control method of front-end detection, first-round proportioning, first-wave material verification, limited water replenishment, and endpoint re-determination, fluctuations in the moisture content of wet sand can be absorbed first in the theoretical proportioning stage, then corrected in the first-wave material stage, ultimately ensuring that each batch of mortar reaches a stable wet state and consistent mixing quality before entering the use station.

[0024] Furthermore, the sampling tube is preferably positioned 150 mm to 500 mm above the discharge gate at the lower part of the wet sand bin. The inner diameter of the sampling tube is preferably 25 mm to 60 mm, the effective volume of the sampling chamber is preferably 30 ml to 120 ml, and the reciprocating stroke of the sampling rod is preferably 80 mm to 220 mm. This facilitates manual maintenance and replacement of the detection unit, and also allows for insertion, extraction, and detection without stopping the main material flow. A scraper ring and a sealing sleeve can also be installed on the outside of the sampling and detection assembly. When the sampling rod is retracted, the scraper ring cleans the mortar and wet sand adhering to the outer surface, reducing the residue accumulation between samples from two consecutive tests. An observation port and a maintenance port are preferably provided at the top of the main mixer. The water injection assembly is staggered with the observation port to prevent the water jet from directly impacting the detection area and causing distortion in the status assessment. A short-section guide channel can also be installed downstream of the discharge section to maintain a relatively concentrated material flow pattern during the verification window, facilitating image recognition or weight fluctuation sampling.

[0025] Specifically, the mortar masterbatch formula, based on an oven-dry standard, includes the following components by weight: 78-82 parts fine aggregate, 11-14 parts cement, 2-4 parts limestone powder, 1-3 parts fly ash, 0.5-1.2 parts hydrated lime, 0.14-0.20 parts cellulose ether, 0.015-0.035 parts starch ether, and 0.20-0.45 parts redispersible latex powder.

[0026] Specifically, the mortar masterbatch formula is constructed using a composite system of cementitious materials, fine aggregates, water-retaining and thickening components, auxiliary anti-slip components, and interface modifiers. The cementitious materials form a strong framework after hardening and provide a base coating for the mortar. The fine aggregates form a volumetric framework and control the required amount of mortar per unit volume. The water-retaining and thickening components improve the retention of free water and the continuity of the mortar film during mixing. The auxiliary anti-slip components enhance the thixotropy of the material and its anti-slip ability during vertical construction. The interface modifiers improve the mortar's coating coordination on the fine aggregate surface and its adhesion to the substrate after hardening. With this component structure, the masterbatch formula no longer relies on a single high-dosage thickening material to maintain the construction state. Instead, through the synergistic effect of the cementitious phase, framework phase, and functional components, fluctuations in the moisture content of wet sand are mainly reflected in the increase or decrease of effective free water, thus facilitating accurate identification during front-end testing and subsequent initial batch verification. The mortar masterbatch formula uses the amount of oven-dried sand converted from wet sand as a uniform basis for batching, so that the fine aggregate volume fraction can remain stable when the moisture content of different batches of wet sand changes. This avoids the imbalance of powder coating ratio caused by directly feeding according to the quality of wet sand, which would amplify the detection error.

[0027] The cementitious material preferably includes at least cement and one or more mineral admixtures. Cement, as the main cementitious component, forms the early and later strength skeleton; ordinary Portland cement or composite Portland cement is preferred, with a strength grade of 32.5, 42.5, or equivalent. The mineral admixture is preferably one or more combinations of limestone powder, fly ash, and hydrated lime. Limestone powder primarily serves as a microfiller and particle size modifier, filling the gaps between cement particles and between fine aggregates and the slurry, resulting in a more continuous slurry film distribution. Fly ash mainly improves the slurry's flowability and particle balling effect, reducing the risk of local agglomeration and facilitating the formation of a uniform wetted layer during the initial mixing stage. Hydrated lime primarily improves the slurry's smoothness, feel, and spreadability, and plays a supporting stabilizing role in the viscoelastic system established by the water-retaining components. The components within the cementitious material are preferably kept in a relatively stable ratio to avoid frequent changes within the same production cycle, thus reducing drift in the water-added model after testing. The total amount of cementitious material should be controlled within a range that allows the slurry to fully coat the fine aggregate without excessive slurry accumulation. When the amount of cementitious material is too low, the first wave of discharge is prone to exposed sand particles and intermittent material flow. When the amount of cementitious material is too high, the stirring current will increase significantly and the recovery time after secondary water replenishment will be longer. Therefore, the master formula should preferably strike a balance between strength requirements and quality control requirements.

[0028] Fine aggregate is controlled using the amount of oven-dried sand converted from wet sand. Fine aggregate is both the main volumetric component and a crucial fundamental component affecting the accuracy of online moisture content correction and the sensitivity of the initial wave material condition identification. The preferred fine aggregate is manufactured sand or a mixture of river sand and manufactured sand. Manufactured sand provides higher skeletal interlocking and surface roughness, making the material more easily exhibit a recognizable dry state when water content is insufficient. River sand improves flowability and interparticle slippage. To ensure a more stable correlation between front-end detection data and actual construction conditions, the fine aggregate is preferably controlled with continuous particle size distribution, maintaining a reasonable proportion between fine, medium, and coarse particles to avoid excessive concentration of a single particle size causing abrupt changes in slurry demand. Too few excessively fine particles in the fine aggregate can cause the slurry to settle easily and the water film on the surface of the initial wave material to be unstable; too many excessively fine particles can cause the free water corresponding to the microwave detection results to decrease too quickly, resulting in a falsely dry initial wave material. Therefore, the fine aggregate is preferably controlled with a continuous gradation suitable for thin-layer plastering or machine-sprayed plastering. After fine aggregate is included in the proportioning as the baseline amount of oven-dry sand, the control components only need to be corrected for the amount of water introduced by wet sand to maintain a stable true mass ratio of powder to aggregate in different batches, making water addition control more repeatable.

[0029] The water-retaining and thickening component includes at least a cellulose ether, preferably hydroxypropyl methylcellulose ether, hydroxyethyl methylcellulose ether, or a cellulose derivative with similar water-retaining and thickening functions. The role of the cellulose ether in the master formulation is mainly reflected in three aspects: first, improving the water-holding capacity of the slurry, preventing the free water formed during the first water addition from migrating in large quantities to the surface of fine aggregates or the inner wall of the equipment in a short period; second, increasing the apparent viscosity of the slurry, enabling the powder and wet sand to quickly establish a continuous slurry film during the first mixing stage; and third, ensuring a more pronounced state recovery characteristic during the re-mixing stage after secondary water addition, avoiding the formation of localized open water zones. The cellulose ether is preferably a medium-to-high viscosity grade material, ensuring it provides a significant water-retaining effect even at low addition levels, while avoiding viscous tailing of the first batch of material during the discharge stage due to excessive viscosity. In addition to the cellulose ether, the water-retaining and thickening component may also include a small amount of compatible auxiliary water-retaining materials, but the main water-retaining effect in the overall formulation is still borne by the cellulose ether to maintain a stable system response. With this setting, when the front-end detection results show that the wet sand is too dry and the planned water addition in the first round is adjusted upwards, the cellulose ether can retain the increased water in the slurry system; when the front-end detection results show that the wet sand is too wet and the planned water addition in the first round is adjusted downwards, the cellulose ether can slow down the excessive water loss caused by the reduction of free water, so that the verification window of the first batch of material still has a certain margin for judgment.

[0030] The auxiliary anti-slip component includes at least starch ether, preferably modified starch ether, etherified starch, or a thixotropic modifier with similar properties. The main function of starch ether is to improve the thixotropic recovery of the mortar under static or low-shear conditions, giving the mortar better anti-slip properties during the short-term residence period after discharge, the adhesion stage after application to the wall, and during vertical surface construction. Compared to cellulose ether, the focus of starch ether is not simply increasing water retention, but rather assisting in establishing a state characteristic of "easy flow during mixing and less sagging during residence," thus making the flow state of the first wave of material more identifiable within the verification window. The amount of starch ether added is preferably lower than that of cellulose ether, so that the main effects of water retention and thixotropy in the master formula are distinguished from each other, avoiding excessive overlap between their functions and parameter drift. When the amount of starch ether added is too low, the first wave of material is prone to collapse too quickly at the discharge end, making it difficult to distinguish between dry and wet states by the appearance of the material flow. When the amount of starch ether added is too high, the first wave of material will still exhibit a certain degree of formability even when there is insufficient effective free water, weakening the sensitivity of the secondary water replenishment triggering logic. Therefore, the auxiliary anti-slip components in the master formula should preferably be maintained within a range that can improve the stability of the material flow without excessively masking the water shortage characteristics.

[0031] The interface modification component includes at least redispersible latex powder, preferably ethylene-vinyl acetate copolymer powder, acrylate latex powder, or polymer powder with similar redispersible film-forming properties. The role of the interface modification component is mainly manifested in two stages: the mixing state and the hardening state. In the mixing state, the redispersible latex powder improves the flexibility and dispersion stability of the slurry when coating sand particles, making the slurry film formed after the first round of water addition more complete and reducing local exposed particles. In the hardening state, the redispersible latex powder improves the mortar's adhesion to the substrate and its resistance to micro-cracking. Since this method involves a controlled process of secondary water replenishment based on the state of the first batch of material after the initial water addition, the redispersible latex powder can also mitigate the risk of interface stratification caused by localized water intrusion after the secondary water replenishment, allowing the remixed slurry to recover to a homogeneous state more quickly. The interface modification component is preferably used in low to medium dosage so that it can play a role in interface coordination and flexible modification, rather than making the whole system into a polymer-dominated elastic material, so as to maintain a clear correspondence between microwave moisture content detection, stirring current change and appearance change of the first wave of material.

[0032] Furthermore, the mortar masterbatch may also include trace auxiliary components that complement the above five types of components. These trace auxiliary components preferably include one or more of the following: defoaming components, water-repellent components, early structural stabilizing components, or microfiber components. Defoaming components reduce the number of large air bubbles introduced during mixing, minimizing the false wet appearance caused by bubble aggregation during the initial material verification stage. Water-repellent components improve water resistance after hardening, but their addition is preferably low to prevent excessive interference with microwave detection response and mixing water distribution. Early structural stabilizing components help restore homogeneity more quickly during the remixing stage after secondary water replenishment. Microfiber components suppress localized settling and enhance material flow continuity. These trace auxiliary components can serve as supplementary components to the masterbatch, but overall, they still belong to the main system composed of cementitious materials, fine aggregates, water-retaining and thickening components, auxiliary anti-slip components, and interface modifying components, without changing the basic structure of the masterbatch centered on wet sand oven-dry conversion and two-stage water addition control.

[0033] Furthermore, the master formula is preferably pre-prepared into uniform dry-mix powder packages, with wet sand added as an independent input component in real-time on the production line. This setup ensures that the cementitious materials, water-retaining and thickening components, auxiliary anti-slip components, and interface modifiers remain constant in each batch. Variations are concentrated in the wet sand moisture content and the resulting effective external water correction, which helps improve the accuracy of the correspondence between the initial batch state parameters and the actual water shortage level. The dry-mix powder packages are preferably stored in sealed silos to prevent moisture absorption from interfering with the front-end wet sand test results. By dividing the master formula into the aforementioned functional components and assigning each component to different roles in skeleton formation, slurry film construction, thixotropic regulation, and interface coordination, the mortar can form a recognizable basic state after the first mixing, exhibiting more stable and quantifiable state differences during the initial batch verification stage. After secondary water replenishment, it can quickly recover to the target working state, thus forming a unified and coordinated relationship with the entire online moisture content detection and stable mixing control method.

[0034] Specifically, the mortar masterbatch formula, based on an oven-dry datum, consists of 78 to 82 parts fine aggregate, 11 to 14 parts cement, 2 to 4 parts limestone powder, 1 to 3 parts fly ash, 0.5 to 1.2 parts hydrated lime, 0.14 to 0.20 parts cellulose ether, 0.015 to 0.035 parts starch ether, and 0.20 to 0.45 parts redispersible latex powder. The proportion of fine aggregate is maintained at 78 to 82 parts, ensuring that the mortar body is always based on a sand skeleton. The cementitious phase and functional components mainly function to coat, lubricate, connect, and regulate the state. This avoids excessive cementitious material content leading to an excessively thick slurry and a rapid increase in stirring current, and also avoids excessive aggregate content leading to insufficient slurry film and a noticeable loose sand feel in the first wave of material window. The cement content should be controlled between 11 and 14 parts to ensure that the hardened base strength, early forming ability, and slurry establishment speed during mixing are within a suitable range for machine-sprayed plastering or stabilized plastering. When the cement content is below this range, the slurry establishment is slower after the first round of water addition, and the first batch of material is prone to obvious particle boundaries, material flow dispersion, and insufficient wall adhesion. When the cement content is above this range, the system is more sensitive to changes in free water. Although the first batch of material makes it easier to identify the water shortage state, the remixing time after the second water addition will be significantly prolonged, and the stable endpoint will appear later, which is not conducive to continuous production.

[0035] The limestone powder content is controlled at 2 to 4 parts, primarily to fill the tiny gaps between cement particles and fine aggregates, improve particle size distribution, and facilitate the formation of a continuous slurry film during the first mixing stage. Simultaneously, the fine powder filling effect enhances the continuity of the material flow during the discharge stage. If the limestone powder content is below this range, the slurry lacks fineness, and the first batch of material is more likely to exhibit a coarse, granular texture within the verification window, which is detrimental to maintaining consistent discharge under the same target condition. Conversely, if the limestone powder content is above this range, it increases the system's short-term water adsorption, leading to a false dryness phenomenon after the first mixing stage, thus increasing the probability of misjudgment triggered by secondary water replenishment. The fly ash content is controlled at 1 to 3 parts, mainly utilizing the rolling lubrication effect of spherical particles to improve mixing coordination and slurry dispersion, allowing wet sand, dry powder, and functional components to form a uniform coating layer more quickly during the first mixing stage. When the fly ash content is too low, the improvement in slurry flow coordination is not significant, and the peak value of the stirring current after the first round of water addition does not decrease sufficiently. When the fly ash content is too high, the early structure establishment is slow, and the first wave of material tends to exhibit a wet and weak flow state in the verification window, affecting the identification of the true degree of water shortage. The hydrated lime content is controlled between 0.5 and 1.2 parts, mainly used to improve the slurry's smoothness and spreadability, enabling the material to have a smoother shear response under the same effective water content, while also assisting the cellulose ether in establishing a more stable water-holding state. When the hydrated lime content is too low, the material tends to exhibit excessive rigidity and insufficient tailing in the first wave of material window; when the hydrated lime content is too high, the system's thixotropic recovery becomes too strong, masking the true flow anomalies caused by water shortage.

[0036] Cellulose ether, controlled at 0.14 to 0.20 parts, is the most important water-retaining and thickening component in this formulation. It is preferable to use hydroxypropyl methylcellulose ether with a medium to high viscosity grade or a water-retaining material with similar properties, so that the slurry forms a stable water film after the first round of water addition and maintains an observable and quantifiable flow pattern within the first wave verification window. When the cellulose ether content is below 0.14 parts, free water easily migrates to the aggregate surface and equipment walls after the first stirring, making the first wave of material more susceptible to environmental disturbances and exhibiting unstable performance within seconds of each batch. When the cellulose ether content is above 0.20 parts, the apparent viscosity of the slurry rises too quickly, and the first wave of material can maintain a certain continuity even with slight water shortage, making it difficult to accurately determine whether secondary water addition is needed through the verification window. Starch ether, controlled at 0.015 to 0.035 parts, is used to improve the anti-slip ability during the settling and low-shear stages, ensuring that the first wave of material maintains a stable strip shape at the edge of the guide channel or discharge port, facilitating continuity and flow pattern identification. When starch ether content is below this range, the initial batch of material is too loose and tends to collapse quickly after discharge, making it difficult to distinguish whether the discontinuity is due to water shortage or insufficient thixotropy. When starch ether content is above this range, the slurry exhibits excessive retention capacity during the initial batch verification stage, easily masking the flow difficulties caused by insufficient actual water content. The redispersible latex powder is controlled at 0.20 to 0.45 parts, primarily serving as an interface coordinator and providing flexible coating. This prevents significant stratification of the slurry film formed after the first round of water addition during secondary water replenishment and re-stirring, while also improving the adhesion coordination after hardening. If the latex powder content is too low, the system is prone to localized insufficient coating after the first round of stirring; if the latex powder content is too high, the polymer characteristics of the material become too strong, weakening the sensitivity of judging water shortage status through current, torque, and discharge pattern.

[0037] To facilitate implementation on the production line, the master formula is preferably prepared as a fixed dry-mix powder package, with fine aggregate added dynamically based on an absolute dry datum as an independent input component. With this setup, the main factors affecting the mixture are the amount of water introduced by the wet sand and the resulting correction for added water. The powder system remains constant, which helps control components to continuously output stable results under the same algorithm. Taking 100 parts of oven-dry total as an example, the preferred central proportion is 80 parts of fine aggregate, 12.5 parts of cement, 3 parts of limestone powder, 2 parts of fly ash, 0.8 parts of hydrated lime, 0.17 parts of cellulose ether, 0.022 parts of starch ether, and 0.30 parts of redispersible latex powder. The characteristic of this central proportion is that a continuous slurry film can be quickly established after the first round of water addition. When the first wave of material is short of water, the material flow cross section is narrow, the current fluctuation is large, and the tail of the guiding section is shortened. When the water volume is appropriate, the material flow is continuous, the cross section is stable, the surface is wet and there is no obvious bleeding. When slightly wet, the material strip edge is shiny and the guiding section spreads too quickly. Thus, the first wave of material window can identify both water shortage and water excess. During production, fine-tuning can be made within the range of each component around this central ratio. For example, limestone powder can be appropriately increased when the proportion of manufactured sand is too low, starch ether can be appropriately increased when the proportion of river sand is too high, and latex powder can be appropriately increased when higher adhesion is required. However, the overall weight range remains unchanged, so that any formula fine-tuning is based on the range that can be identified by online moisture content correction and first wave material verification.

[0038] Furthermore, before entering the production line, the master formula preferably undergoes dry-mix pre-homogenization treatment, with a dry-mixing time preferably between 90 and 240 seconds. This ensures that cellulose ethers, starch ethers, and redispersible latex powder are evenly distributed between the cementitious materials and fine powder particles, preventing localized enrichment upon initial contact with moisture. After dry mixing, the master formula is preferably stored in a sealed powder silo, with an ambient relative humidity preferably not exceeding 70%, to reduce interference from pre-moisture absorption by the powder on the initial planned water addition. During the mixing stage, the master formula and the converted wet sand are preferably fed into the machine within 5 seconds, allowing cement, fine powder, and functional components to simultaneously contact the initial planned water addition, reducing localized differences caused by early or late wet addition. By unifying the formula range, dry-mix homogenization state, feeding sequence, and subsequent two-stage water addition process, this master formula not only possesses basic construction performance but also process adaptability for online moisture content detection, initial batch verification, and quality stabilization endpoint determination. This provides a stable basis for setting specific detection times, mixing times, and water addition amounts in subsequent embodiments.

[0039] Specifically, wet sand is manufactured sand or a mixture of river sand and manufactured sand. Wet sand meets at least some of the following conditions: fineness modulus is 2.5 to 2.9, stone powder content is 4.0% to 7.5%, mud content is not higher than 1.2%, and the working range of online detection moisture content is 3.0% to 8.5%.

[0040] Specifically, the wet sand is preferably manufactured sand or a mixture of river sand and manufactured sand. Before entering the mixing system, the wet sand is first screened and stabilized, and then buffered for a short time to ensure that the flow state of the material entering the sampling and testing position and the metering position is as consistent as possible. When using pure manufactured sand, crushed sand with relatively stable parent rock composition and low content of needle-like and flaky particles is preferred. This is because crushed sand has rough particle surface, adjustable gradation, and strong support for the slurry skeleton. This allows the material to show more obvious differences in appearance and mixing resistance under the two states of water shortage and water supply after the first round of mixing. When using a mixture of river sand and manufactured sand, river sand is preferred to provide rounded particles and basic flow coordination, while manufactured sand provides particle interlocking and sensitivity to changes in slurry thickness. This ensures that the material is neither too slippery nor too dry, making it easier to identify the actual water content deviation through material flow pattern, current fluctuation, and wetness state within the first wave of material verification window. The fineness modulus of wet sand is controlled between 2.5 and 2.9. On the one hand, this ensures that the overall particle size distribution of fine aggregate is within a range suitable for plastering mortar, machine-sprayed mortar, or stabilized thin-layer mortar, guaranteeing that cementitious materials and functional components can form a continuous slurry film under reasonable water content. On the other hand, it keeps the surface area of ​​sand particles and the amount of slurry required for coating within a predictable range, avoiding excessive fine particles and rapid adsorption of free water due to a low fineness modulus, resulting in false dryness. It also avoids excessive coarse particles and insufficient slurry film continuity due to a high fineness modulus, which can cause breakage and dispersion of the first wave of material in the early stage of discharge.

[0041] The stone powder content is preferably controlled between 4.0% and 7.5%, where stone powder mainly refers to fine powder associated with manufactured sand with a particle size of less than 0.075 mm or micro-particles retained after shaping and grading. When the stone powder is within this range, some of it can fill the tiny gaps between cement, mineral admixtures, and fine aggregates, improve particle size distribution, and increase the density of the slurry, making the slurry film formed after the first mixing more complete, and the first wave of material exhibits a more stable material strip boundary at the front end of the guide channel or discharge port; another part of the stone powder participates in regulating the short-term water-holding state, making the effective free water distribution formed by the water brought in by the wet sand and the planned water addition in the first round more uniform. If the stone powder content is below 4.0%, the slurry will lack fineness, and the surface of the first batch of material will be more prone to exposed sand particles and a rough feel. The re-stirring time required to restore a uniform state after secondary water replenishment will be longer. If the stone powder content is above 7.5%, the short-term adsorption effect of fine powder on free water will be enhanced. At the end of the first round of stirring, the surface may appear dry but the interior may not be truly dry, increasing the risk of misjudgment in the first batch of material verification stage. Therefore, limiting the stone powder content to the above range is conducive to maintaining a relatively stable correspondence between the online moisture content detection results and the state parameters of the subsequent first batch of material. The mud content is controlled to be no higher than 1.2% to limit the superimposed interference of clay impurities and mud lumps on microwave detection, stirring resistance and slurry rheology. When the mud content is too high, the water absorption hysteresis and plastic deformation characteristics of mud particles will mask the true water content of wet sand, causing different batches of material at the same water content to show significantly different appearances and current signals of the first wave of material. Therefore, it is preferable to reduce the mud impurity content by washing, grading, desliming or settling before the wet sand enters the production line, and then combine it with online detection for dynamic proportion control.

[0042] The optimal operating range for online moisture content detection is 3.0% to 8.5%. This range covers common moisture states of wet sand in conventional mortar production affected by climate, stockpile conditions, and spraying, while ensuring that the initial planned water addition and reserved correction water amount remain within an adjustable range. When the real-time moisture content of wet sand is below 3.0%, the wet sand is closer to a dry sand state. Although the sampling and testing results can be used for conversion, the initial water addition will account for a large proportion of the target total water consumption, and the material is more sensitive to the water replenishment rhythm. In this case, it is preferable to shorten the sampling interval and appropriately increase the proportion of the initial water addition. When the real-time moisture content of wet sand is above 8.5%, the proportion of free water inside the wet sand is higher, and the sand particles in the silo are more likely to form short-term agglomerations and adhere to the walls. There may be a deviation between the sampling and testing results and the average state actually entering the mixer. In this case, it is preferable to add a flow stabilizing and arch-breaking mechanism, a vibration auxiliary mechanism, or a flow guiding and shaping section at the bottom of the wet sand silo, and to perform a short-term discharge before sampling to make the test sample closer to the actual production state. In a preferred embodiment, the control component can further divide the 3.0%–8.5% working range into a low-humidity zone of 3.0%–5.0%, a medium-humidity zone of 5.0%–6.8%, and a high-humidity zone of 6.8%–8.5%. Different sampling frequencies, first-round mixing times, and first-wave material verification sensitivity thresholds are used in different zones. For example, in the high-humidity zone, the judgment weight of the discharge continuity and wet appearance in the first-wave material window is appropriately increased, and in the low-humidity zone, the judgment weight of the mixing current fluctuation and material strip integrity is appropriately increased, so that the same set of master formulas can maintain stable judgment accuracy under different wet sand conditions.

[0043] Furthermore, the wet sand preferably undergoes at least one short-range homogenization treatment before entering the metering hopper or mixer. This short-range homogenization can be achieved through one or more of the following methods: natural discharge from a buffer hopper, spiral feeding homogenization, or short belt spreading and shaping. This allows for a preliminary redistribution of locally high-moisture clumps and relatively dry sand before they reach the sampling and metering positions, reducing the randomness of single-point sampling. To ensure a clearer correlation between microwave detection results and actual water correction values, the wet sand should preferably avoid the inclusion of heterogeneous particles with significant abrupt changes in particle size, sand clumps still containing surface water after prolonged soaking, and excessively wet sand that has not been fully drained after washing. When significant stratification is unavoidable in the stockpile, the wet sand silo is preferably designed with a multi-point discharge structure, and a guide cone or buffer plate is installed inside the silo to allow sand from different moisture levels to mix during the discharge process before sampling and testing. After adopting the above-mentioned wet sand conditions, the data obtained from the front-end moisture content test can better represent the average moisture state of the current batch entering the mixer. The fineness modulus, stone powder content, mud content and working moisture content range are also easier to keep within the preset range. This makes the entire process of calculating based on the absolute dry sand benchmark, allocating the first round of planned water addition and reserved correction water according to the theoretical total amount of added water, and judging whether secondary water addition is needed within the first wave of material verification window have higher repeatability and stability.

[0044] Specifically, in step S2, the initial planned water addition and the reserved correction water addition are determined based on the difference between the target total water consumption and the water carried in by the wet sand. The water carried in by the wet sand is calculated based on the real-time moisture content data of the wet sand and the amount of wet sand fed. Let the baseline quantity of absolutely dry sand be The real-time moisture content of the wet sand is W, where W is the mass fraction based on the total mass of the wet sand, and the target total water consumption is... , The actual amount of wet sand fed for: ; Water carried in by wet sand for: ; Theoretical total additional water for: ; First round of planned water addition for: ; Reserved correction water volume for: ; in, This is the coefficient for the first round of water addition, and .

[0045] Specifically, the initial planned water addition and reserved correction water addition in step S2 are determined based on the difference between the target total water consumption and the water content introduced by the wet sand. Preferably, the calculation is performed using an oven-dry conversion method based on the wet basis moisture content. After receiving the real-time moisture content data of the wet sand from the microwave detection unit, the control component first treats this moisture content as the water mass percentage in the total mass of the wet sand, setting the oven-dry sand baseline quantity as... The real-time moisture content of the wet sand is W, where W is the mass fraction based on the total mass of the wet sand, and the target total water consumption is... The actual amount of wet sand fed in the current batch According to the formula The calculation indicates that, in order to ensure that the quality of the oven-dry sand entering the mixing system remains stable at the preset value, the actual amount of wet sand to be added needs to be calculated based on the current measured moisture content; the amount of water brought in by the wet sand. According to the formula The calculation represents the total amount of water already carried into the mixing system by the current batch of wet sand; the theoretical total amount of additional water. According to the formula The calculation represents the amount of water that still needs to be added to achieve the total target water consumption required by the master formula, assuming that some moisture has already been introduced into the wet sand; the initial planned water addition. According to the formula Calculate and reserve correction water volume According to the formula Calculation, where This is the initial water addition coefficient. With this setting, the higher the moisture content of the wet sand, the greater the amount of water introduced by the wet sand, and the smaller the theoretical total amount of water added; the lower the moisture content of the wet sand, the smaller the amount of water introduced by the wet sand, and the larger the theoretical total amount of water added. The entire calculation process revolves around the baseline amount of oven-dry sand, so that the same masterbatch formula maintains the true aggregate baseline unchanged under different wet sand conditions.

[0046] To improve the consistency between the formula calculation and the actual production state, the real-time moisture content data of wet sand is preferably not directly used in the calculation from a single instantaneous value, but rather a representative value is obtained through continuous sampling or multiple short-term sampling. Preferably, two to five consecutive sampling tests are performed before the start of the same batch of materials. The obtained wet sand moisture content data is then processed by moving average, median value screening, or extreme value removal averaging in chronological order, and the processed representative moisture content is used as W in the calculation. When the difference between two adjacent test values ​​exceeds a preset threshold, the control component preferably triggers supplementary sampling or delayed feeding to avoid local high-moisture sand clumps or local dry sand layers in the silo directly affecting the water addition calculation of this batch. Further, the preset threshold can be set according to the absolute difference in moisture content of 0.3% to 1.0%, or it can be set according to the relative fluctuation ratio, so that the test results reach a stable state before entering the conversion formula. By performing short-term stabilization processing on the real-time moisture content data of wet sand, it is possible to... , , and The calculation results are closer to the actual average working conditions, reducing the amplified impact of a single accidental sampling on the first-round condition of the entire batch of mortar.

[0047] Target total water consumption Preferably, the master formula is predetermined and corresponds to the baseline amount of oven-dry sand, the total amount of cementitious materials, the dosage of water-retaining and thickening components, and the target construction state. Preferably, for the same central formula and the same target construction state, The settings remain unchanged throughout a production cycle, only being reset when the masterbatch formula is changed, the application is altered, or the target discharge state is altered. With this setup, the entire online correction process primarily revolves around changes in the amount of water carried in by the wet sand, resulting in clearer control logic. Furthermore, it is also possible to... Based on this, a small correction factor is introduced. This correction factor is preferably related to the ambient temperature, powder loading temperature, wet sand temperature, or the deviation of the previous batch's stabilization endpoint. The calculation expands from a fixed target value to the sum of the basic target value and the process correction value. However, regardless of whether a fixed target total water consumption or a corrected target total water consumption is used, its participation in subsequent calculations remains the same: it is calculated first. Calculate again Then split and .

[0048] In practical implementation, the control component preferably incorporates outlier detection logic to ensure that the formula calculation result always falls within the executable range. When the calculated result... When the water content is less than or equal to zero, it indicates that the water introduced by the wet sand has reached or exceeded the target total water consumption. In this case, it is preferable to suspend the external water input and output a high humidity warning signal to the upper control interface. Simultaneously, one or more of the following operations can be performed: reducing the wet sand feeding speed, switching to the dehumidification buffer chamber, extending the idling homogenization time, or re-sampling and retesting. When the calculated... When the flow rate is greater than zero but lower than the preset minimum threshold for the first round of water addition, it is preferable to perform the first round of planned water addition according to the minimum controllable water addition pulse to avoid unstable operation of the valve assembly under excessively low flow rates; when the calculated... When the feed exceeds the allowable upper limit of the metering hopper or feeding mechanism, it is preferable to use a multi-stage or batch feeding method to ensure that the baseline amount of oven-dried sand still accurately reaches the preset value. Furthermore, it is also possible to... and Corresponding to the valve group opening duration or flow pulse count, for example, the primary water supply valve group is converted into continuous opening time or pulse jet count based on the planned water supply volume for the first round, and the secondary water supply valve group is set with the maximum allowable total opening time based on the reserved correction water volume, so that the calculation results are directly converted into actuator action parameters. By linking the formula calculation results with anomaly judgment, valve group control and metering upper limit, step S2 can not only remain at the mathematical conversion level, but also directly drive the actual production line to complete the first round of water distribution and reserved correction water volume allocation.

[0049] Furthermore, to improve the correlation between the initial planned water addition and the reserved correction water amount and the subsequent verification results of the first batch of materials, the control component preferably saves the W values ​​of the current batch. , , and The initial batch material's state parameters, along with the required continued mixing time to reach the stabilization endpoint, the actual secondary water replenishment amount, and the final discharge state, are stored in the batch database. When the current batch and the next batch use the same master formula, have the same source of wet sand, and similar environmental conditions, the control component can retrieve data from the most recent batches to optimize the current batch. or A small-scale pre-correction is performed to make the front-end formula calculation result closer to the actual state of the first batch of material in the back-end. For example, if several consecutive batches show that the first batch of material is too dry and triggers secondary water replenishment under similar W conditions, the control component can appropriately increase the first-round water addition coefficient in the next batch. When several consecutive batches exhibit shiny edges and excessively rapid material spread in the high-humidity range, eliminating the need for secondary water replenishment, the control unit can appropriately reduce the humidity in the next batch. Or tighten The upper limit.

[0050] Specifically, the first round of planned water addition in step S3 Theoretical total additional water 82%–90% of the water volume is reserved for correction. Theoretical total additional water 10% to 18%.

[0051] Once the initial planned water addition falls within this range, a continuous slurry film and basic flow state can be established first during the initial mixing stage. This allows the wet sand, cementitious materials, and functional components to quickly form a cohesive mass, while preserving sufficient room for subsequent corrections. This avoids over-watering in the first round, which would render the initial material verification window meaningless, and also avoids under-watering, which would result in an overall dry mass and increased local clumping after the first round of mixing. When the initial planned water addition is less than 82% of the theoretical total water addition, the initial material is prone to discontinuous discharge, significant shrinkage of the material strips, high current in the mixing motor, and localized dry core residues after the first mixing. This increases the burden of subsequent secondary water replenishment and prolongs the mixing time after water replenishment. When the initial planned water addition is more than 90% of the theoretical total water addition, the differences in the initial material window that can be used to identify the true water shortage state are compressed. If there is a detection deviation in the real-time moisture content of the wet sand or if locally high-moisture clumps from the wet sand bin enter the mixing system, the initial water addition is more likely to result in surface shine, excessively rapid material spread, and localized over-watering, reducing the stability of subsequent limited corrections. By limiting the amount of water added in the first round of the plan to the above-mentioned ratio range, the material after the first mixing can be in a state of "basic formation but still correctable", which not only has the identifiability required for the verification of the first batch of material, but also retains the space for state recovery after the second water replenishment.

[0052] The initial water addition is preferably a combination of continuous water addition and a short-term final water addition. Most of the planned water volume for the first round is added in the initial period after the main mixer receives the material, with the remaining small portion added in the middle to early stages of the first mixing. This allows the water to quickly wet the powder and sand surface, gradually establishing a uniform slurry film during subsequent mixing. Preferably, 70%–85% of the planned water volume for the first round is added within 2–12 seconds after the material is fed in, with the remaining 15%–30% added in the subsequent 5–20 seconds. This avoids both initial localized water accumulation and a completely dry grinding state in the later stages. The preferred water addition method is multi-point spraying or multi-nozzle atomization along the length of the mixer, ensuring a more uniform distribution of the planned water volume in the transverse and longitudinal directions of the material, reducing localized areas of abundant or scarce water caused by single-point water addition. During the first mixing process, the control components can simultaneously monitor the rising and falling phases of the mixing motor current. When the planned amount of water added in the first round falls within the above-mentioned ratio range, the current signal preferably shows a significant rise first, and then gradually falls back and enters a relatively stable range after wetting and mixing are completed, indicating that the material is transitioning from discrete particles to a continuous slurry film coating state.

[0053] The reserved correction water volume is limited to 10%–18% of the theoretical total additional water, used for limited correction of the actual material state within the initial batch verification window. When the reserved correction water volume is within this range, secondary water replenishment can effectively compensate for the slightly dry state caused by factors such as front-end detection deviations, uneven local moisture distribution in the wet sand bin, and short-term uneven distribution during the first mixing stage, without the secondary water replenishment itself becoming a new source of excess water due to excessive replenishment. When the reserved correction water volume is less than 10% of the theoretical total additional water, even if a significant water shortage is identified during the initial batch verification, the subsequent water replenishment adjustment range will be limited. The reserved correction water volume is limited to 10%–18% of the theoretical total additional water, used to make limited corrections to the actual material state within the first batch of material verification window. When the reserved correction water volume is within this range, secondary water replenishment can effectively compensate for the dry state caused by factors such as front-end detection deviations, uneven local moisture in the wet sand bin, and short-term uneven distribution during the first mixing stage, without the secondary water replenishment itself becoming a new source of water overflow due to excessive water replenishment. When the reserved correction water volume is less than 10% of the theoretical total additional water, even if a significant water shortage is identified in the first batch of material verification, the subsequent water replenishment adjustment range will be too small, easily resulting in a situation where the mixing time still needs to be extended after water replenishment, but the material state is still not fully restored. When the reserved correction water volume is more than 18% of the theoretical total additional water, although the theoretical subsequent adjustment margin is larger, the planned water volume in the first round is correspondingly smaller. After the first mixing, the material is more likely to be dry overall, and the state fluctuation in the first batch of material window is also larger, which is not conducive to stable judgment. By controlling the reserved correction water volume within the above range, the secondary water replenishment can always be used as a limited correction measure for the condition of the first wave of material, rather than replacing the first round of planned water replenishment to undertake the main forming function.

[0054] The first mixing preferably includes a wetting stage and a homogenization stage. The wetting stage is used to ensure sufficient contact between the planned initial water addition and the wet sand, cementitious materials, and functional components. The homogenization stage is used to establish a continuous slurry film and eliminate local dry nuclei. The wetting stage preferably lasts 15 to 30 seconds, and the homogenization stage preferably lasts 20 to 45 seconds. The total duration of the first mixing is preferably controlled between 35 and 75 seconds. When the total duration of the first mixing is less than 35 seconds, although the planned initial water addition has been completed, the coating layer formed on the surface of the wet sand is not yet sufficient, and the first batch of material is prone to random deviations due to local incomplete mixing. When the total duration of the first mixing is more than 75 seconds, the internal state of the material tends to be over-homogenized, and the sensitivity of the first batch of material window to the early water shortage state is reduced. After the first mixing, the material preferably enters a state where it can be discharged but has not yet been finally determined. In this state, the first batch of material can reflect whether the front-end moisture content detection and the planned initial water addition match, while also retaining limited space for correction by reserving correction water.

[0055] The initial planned water addition and the reserved correction water addition are preferably controlled by separate water addition loops. The initial water addition loop preferably uses a continuous main water valve or a high-flow pulse valve assembly, while the secondary water replenishment loop preferably uses a low-flow fine-tuning valve or a multi-short-pulse injection valve assembly. The initial water addition loop is used to quickly and stably input the initial planned water addition, enabling the initial mixing to rapidly establish the basic slurry state. The secondary water replenishment loop is used for limited correction after the initial material verification, ensuring that the added water is dispersed into the material body with high precision. With separate control of the initial and secondary water additions, the control component can set the valve opening duration, instantaneous flow rate, and total injection volume for each water addition stage, avoiding control errors caused by the same valve assembly simultaneously handling both rapid and fine water replenishment functions. Preferably, the instantaneous flow rate of the first water addition circuit is greater than that of the second water replenishment circuit, the spray coverage of the first water addition circuit is greater than that of the second water replenishment circuit, and the second water replenishment circuit is preferably arranged closer to the high-shear area of ​​the main mixer so that the added water can be dispersed and absorbed more quickly during the continued mixing stage.

[0056] Under continuous production conditions, the initial planned water addition and the reserved correction water amount can also be used in conjunction with the real-time moisture content range of the wet sand. When the real-time moisture content of the wet sand is near the lower limit of the working range, the initial planned water addition should preferably be taken closer to the proportion of the theoretical upper limit of the total added water, and the reserved correction water amount should be correspondingly smaller, so that the material can quickly establish a continuous slurry film after the first mixing. When the real-time moisture content of the wet sand is near the upper limit of the working range, the initial planned water addition should preferably be taken closer to the proportion of the theoretical lower limit of the total added water, and the reserved correction water amount should be correspondingly larger, so that the first batch of material verification still has sufficient correction space. With this method, the material at different moisture levels can enter a similar basic state range at the end of the first mixing, reducing the extreme cases of excessive dryness in the low moisture zone and excessive wetness in the high moisture zone, thereby making the state parameters in the first batch of material verification window more consistent.

[0057] Furthermore, the control component preferably records the start and end times of the first water addition, the start and end times of the first mixing, and the maximum allowable water replenishment corresponding to the reserved correction water volume for each batch, and saves these records in relation to the state parameters of the first wave of material and the time when the final stable quality endpoint is reached. When adjacent batches use the same master formula and the source of wet sand is consistent, the control component can fine-tune the ratio of the planned water addition in the first round to the reserved correction water volume based on the performance of the first wave of material in the most recent batches, so that the same production line can maintain a more stable first forming capacity and subsequent correction capacity in long-term operation. By limiting the planned water addition in the first round to 82% to 90% of the theoretical total water addition and the reserved correction water volume to 10% to 18% of the theoretical total water addition, the first mixing can prioritize the completion of the main forming, the first wave of material verification undertakes the state identification, the second water replenishment undertakes limited correction, and the continued mixing undertakes the final homogenization, thus giving the entire automatic mortar proportioning and stable mixing control process a clear segmented function and a stable process response.

[0058] Specifically, the preset first wave material verification window in step S4 is a preset time interval or preset discharge volume interval after the start of material discharge, and the actual secondary water replenishment volume in step S5 is not higher than the reserved correction water volume. The preferred total water consumption is... 2% to 4%.

[0059] Specifically, the preset first-wave material verification window in step S4 is a preset time interval or preset discharge volume interval after the start of discharge. The actual secondary water replenishment volume in step S5 is no higher than the reserved correction water volume, preferably 2% to 4% of the target total water consumption. The first-wave material verification window is set at the beginning of the discharge stage to quickly judge the actual state after the first mixing before the entire batch of mortar has been discharged, so that the initial material state corresponding to the online moisture content detection and the first round of planned water addition can be verified in the shortest path. The first-wave material verification window is preferably set to 3 to 12 seconds after the start of discharge. Within this time range, the material state formed after the first round of mixing has not been significantly affected by long-term discharge disturbance, environmental water loss, and subsequent material layer compression, and can more realistically reflect the immediate quality state of the current batch after the first mixing. The first-wave material verification window can also be set to the stage of the first 5% to 15% of the total discharge volume, so that the verification logic can be kept consistent in a relative proportion under different output, different batch specifications, and different discharge speed conditions. If the verification window for the first wave of material is too early, the material body is subjected to a large impact from the start and stop of the discharge mechanism, and the mechanical disturbance is easily mistaken for an abnormal state. If the verification window for the first wave of material is too late, the entire batch of material has already gone through a long discharge process, and the first wave of material no longer represents the initial state after the first mixing. The timeliness of the window judgment and the significance of correction will both decrease.

[0060] The preset verification window for the first wave of material should be further refined based on the production line's discharge method and the material's intended use. When using a continuous discharge structure, the verification window should ideally be limited by both a time interval and a discharge volume interval. Specifically, a fixed time period after the start of discharge should be used as the main window, and the proportion of the cumulative discharge volume within that time period to the total target batch volume should be used as the verification condition. This ensures both uniformity of equipment cycle time and adaptability to batch size during the verification phase. When using a batch-type open-door discharge structure, the verification window should ideally focus on the cumulative discharge volume interval, allowing for smoothing of differences between the initial door opening stage, the material layer descent acceleration stage, and the stable discharge stage. For production lines with high material flow rates, a shorter time and a lower discharge ratio are preferred for the first wave of material verification window. For production lines with high material viscosity, long guide sections, or a discharge mechanism with a buffer structure, the first wave of material verification window should ideally be appropriately shifted and extended to ensure that the material entering the detection area has formed a stable flow. By setting the first wave of material verification window to the controlled range at the beginning of the discharge stage, the actual test object can always correspond to the "first batch of formed material after the first mixing is completed", thereby improving the correspondence between the secondary water replenishment trigger logic and the actual water shortage degree.

[0061] The fact that the actual secondary water replenishment in step S5 is not higher than the reserved correction water volume indicates that the secondary water replenishment is always completed within the limited adjustment space reserved after the first round of planned water addition. The actual secondary water replenishment does not replace the first round of planned water addition as the main water addition function. The actual secondary water replenishment volume is preferably output in stages by the control component based on the degree to which the state parameters of the first batch of material deviate from the target range. When the state parameters of the first batch of material are only slightly lower than the preset target range, the actual secondary water replenishment volume is preferably a smaller portion of the reserved correction water volume. When the state parameters of the first batch of material are significantly lower than the preset target range and are accompanied by high stirring current, intermittent material flow, or a rough surface of the first batch of material, the actual secondary water replenishment volume is preferably close to the upper limit of the reserved correction water volume. By limiting the actual secondary water replenishment volume to no more than the reserved correction water volume, each batch of mortar can first complete the main water distribution according to the front-end test results, and then the first batch of material verifies that only limited correction is performed, thus maintaining a clear hierarchy in the entire control process. If the actual secondary water replenishment exceeds the reserved correction water volume, it indicates that the first water addition ratio or the front-end test result has deviated from the normal control range. This can easily cause subsequent water replenishment to evolve from limited correction to a new dominant water addition, which is not conducive to keeping each batch of mortar running under the same control model.

[0062] The optimal amount of secondary water replenishment is 2% to 4% of the target total water volume. This range ensures that the water replenishment is sufficient to correct the slightly dry state identified in the initial batch of material, without causing excessive water replenishment that could lead to surface water enrichment, localized slurry-water separation, or sudden changes in the subsequent mixing load. If the actual secondary water replenishment is less than 2% of the target total water volume, it can still improve slightly dry conditions. However, if the initial batch of material has insufficient continuity, limited flow expansion, or significantly high current fluctuations, the water replenishment correction effect may be insufficient, resulting in failure to reach the stable quality endpoint after continued mixing. If the actual secondary water replenishment is more than 4% of the target total water volume, although the material's wettability increases rapidly in the short term, it is more likely to create a secondary water-rich zone due to concentrated water entering localized areas, increasing the homogenization burden during the continued mixing stage. Setting the actual secondary water replenishment to 2% to 4% of the target total water volume allows for more precise adjustment rather than coarse compensation, and enables the continued mixing stage to primarily perform the function of "rapid homogenization" rather than "reshaping."

[0063] In practice, secondary water replenishment is preferably achieved using multiple short-pulse injections or short-duration continuous injections. When the initial material's state parameters just trigger the water replenishment threshold, a single, smaller water replenishment pulse is preferred, followed by a short period of continued mixing before re-reading the state signal. When the initial material's state parameters are significantly lower than the target range, the main water replenishment is preferably completed in one go within the reserved correction water volume range before proceeding to the continued mixing stage. Secondary water replenishment is preferably input along the high-shear region of the main mixer, the multi-blade intersection region, or near the material tumbling path, ensuring that the added water is dispersed throughout the slurry in the shortest possible time. The secondary water replenishment valve assembly preferably employs a valve body structure with fast response speed and stable minimum control flow, and establishes a pulse width or opening duration correspondence with the control components to ensure that the actual secondary water replenishment volume is executed precisely according to the set value. When the first wave of material verification window is combined with the upper limit of secondary water replenishment, the optimal ratio of secondary water replenishment, and the water replenishment input method, the same master formula can maintain a stable initial forming state and controllable subsequent correction capability under different wet sand moisture content conditions. This enables the mortar to have both detection-driven front-end proportioning accuracy and first wave of material verification-driven end-end fine-tuning capability in continuous production.

[0064] Specifically, the first wave material status parameters in step S4 include one or more of the following: discharge end humidity value, stirring motor current fluctuation value, stirring torque change value, first wave material flow expansion value, and discharge continuity parameters.

[0065] After setting the state parameters of the first wave of material to multiple different types of detection quantities, the mortar after the first mixing can be comprehensively characterized from the perspectives of water content, mixing load, material flow morphology, and discharge stability. This allows the verification of the first wave of material to improve the stability of the judgment by not relying on a single test result, but by verifying the mutual correlation between different parameters. The discharge end humidity value directly characterizes the instantaneous moisture content of the first wave of material when it enters the guide section or leaves the discharge port. It is preferably obtained using a short-range microwave probe, a capacitive probe, or a small-volume sampling and retesting unit. The stirring motor current fluctuation value characterizes the change in internal resistance of the material during the stirring process. When the material is too dry, the slurry film is not continuous, or there are many local agglomerations, the current signal usually shows a higher average value and a larger fluctuation amplitude. The stirring torque change value characterizes the changing trend of the resistance encountered when the stirring component pushes the material to turn over. When combined with the current signal, it can more accurately reflect the degree of material transformation from a discrete particle state to a continuous slurry state. The first wave of material flow expansion value characterizes the natural spreading ability and extension state of the material after leaving the discharge port. It can be calculated by the material strip expansion distance in the length direction of the guide channel, the spreading width after free fall, or the flow radius after short-term restricted flow. The discharge continuity parameter characterizes whether the first wave of material falls or flows out continuously, stably, and uniformly within the verification window. It can be obtained through image recognition, weight change curves, photoelectric blocking frequency, or the integrity of the material strips on the surface of the guide channel. After using one or more of the above parameters as the status parameters of the first wave of material, the status recognition in the verification window of the first wave of material changes from "whether it looks too dry" to "whether it has reached the quantifiable target range".

[0066] The humidity value at the discharge end is preferably located in the front area of ​​the guide section below the discharge port or in a position around the discharge port that is not easily obstructed by a large area of ​​material pile, so that the sensor can obtain a continuous and representative humidity response when the first wave of material flows through. When using a microwave probe, the microwave signal penetrates the surface and shallow internal areas of the first wave of material, and the humidity value is obtained by utilizing the effect of changes in moisture content on microwave attenuation and phase shift. When using a capacitive probe, the moisture content level is indirectly reflected by measuring the change in the dielectric constant of the material. When using a small-volume sampling and retesting unit, a small amount of mortar sample can be briefly intercepted within the window of the first wave of material and entered into the detection chamber, and then the humidity value is calculated by microwave or weighing. The humidity value at the discharge end preferably adopts continuous sampling and short-time averaging to reduce the instantaneous deviation caused by local water, air bubbles, or single sand clumps on the surface of the first wave of material passing through the detection area. Preferably, the control component sets upper and lower limit target ranges for the humidity value at the discharge end. When the detected value is below the lower limit, it is determined that the first wave of material has a tendency to be insufficient in effective free water; when the detected value is above the upper limit, it is determined that the first wave of material has a tendency to be too wet or locally rich in water; when the detected value is within the target range, it indicates that the humidity of the first wave of material after the first mixing has met the preset requirements. By incorporating the humidity value at the discharge end into the state parameters of the first wave of material, the verification of the first wave of material can directly have online feedback capability for the moisture content, forming a two-stage moisture judgment chain that echoes the front-end wet sand moisture content detection.

[0067] The current fluctuation value of the mixing motor is preferably collected continuously at the end of the first mixing stage, the beginning of the discharge stage, and the continued mixing stage after the second water replenishment, and recorded in the control component at a preset sampling frequency. The current fluctuation value can be expressed as the difference between the instantaneous maximum and minimum current values, the short-term root mean square fluctuation value, the number of peaks and troughs per unit time, or the normalized fluctuation amplitude. After the first mixing, if the material has formed a relatively stable slurry film, the current fluctuation value is preferably gradually decreasing and tending to stabilize; if the material is too dry, has a lot of local agglomeration, or has high sand particle friction resistance, the current fluctuation value will remain at a high level and continue this characteristic during the first wave of material window. When the current fluctuation value of the mixing motor is used in conjunction with the humidity value at the discharge end, it can distinguish the situation of "apparent humidity close to the target but there are still local dry nuclei inside". That is, when the humidity value at the discharge end is in the target range but the current fluctuation is still significantly high, it can be judged that the internal homogeneity of the material is insufficient, and it can still be used as an important basis for judging the second water replenishment or continued mixing. Preferably, the control component pre-records the current fluctuation reference curves of the same master formula under the conditions of sufficient water, slightly dry and slightly wet, so that the current fluctuation values ​​read during the verification of the first batch of materials can be directly compared with the reference curves, thereby improving the consistency of the judgment.

[0068] The stirring torque variation value is preferably obtained through a torque sensor on the main mixer drive shaft, a load conversion module at the reducer output, or a servo drive feedback module. This value characterizes the resistance change when the mixing components push the mortar material to tumble. The torque variation value can be expressed as average torque, peak torque, short-term fluctuation range, or the rate of change between adjacent sampling points. When the material is in a suitable moisture content range, the stirring torque preferably shows a gradual decrease after the initial mixing to establish the slurry film, maintaining a relatively flat trend before and after the first wave verification window. When the material is relatively dry, the peak torque is higher and the rate of decrease is slower, indicating that the slurry's coating of the aggregate is still insufficient. When the material is relatively wet, the torque decreases too quickly and remains below the normal reference range, indicating insufficient slurry flow resistance, which may lead to excessive spreading later. When the stirring torque variation value is used simultaneously with the stirring motor current fluctuation value, the state of the first wave of material can be double-checked from a mechanical load perspective, reducing misjudgments caused by fluctuations in motor operating conditions affecting a single electrical signal. The torque change value can also be used to judge the state recovery process after secondary water replenishment. When the torque gradually returns to the target range and remains stable within the preset time of continued stirring after water replenishment, it indicates that the added water has been evenly absorbed and the internal turning resistance of the material has reached the normal level.

[0069] The flow spread value of the first wave of material is preferably obtained through a guide plate, a flat receiving plate, or a standard short trough section located downstream of the discharge port. When the first wave of material flows through the guide plate, the image recognition module can record the advancing distance of the material strip's leading edge, the width of the material strip's boundary, the tail length of the material strip's end, and the natural spreading angle, and convert these into a flow spread value. When the first wave of material lands on the flat receiving plate, it can be represented by the spreading area per unit time, the maximum spreading width, or the outer edge spreading radius. When using a standard short trough section, it can also be comprehensively calculated by the continuous filling length of the material flow in the trough and the spreading length after exiting the trough. A smaller flow spread value of the first wave of material indicates lower free water content, a thinner slurry film, or higher structural resistance. A larger flow spread value indicates higher free water content or a thicker surface slurry. Since the flow expansion value of the first wave of material directly reflects the external flow performance of the material under low or unconstrained conditions, it can be used in conjunction with the discharge end humidity value, the stirring motor current fluctuation value, and the stirring torque change value to characterize whether the first wave of material has reached the target state from both appearance and internal resistance perspectives. Preferably, a standard flow expansion range is set for the same master formula, and independent flow expansion reference values ​​are established for different sand sources and different center proportions, so that the determination of the flow expansion value of the first wave of material is more in line with actual production conditions.

[0070] The discharge continuity parameter is preferably acquired through an image acquisition device below the discharge port, a weight sensor, a photoelectric detector, or a vibration response module of the receiving trough. When using an image acquisition device, it can identify whether the first wave of material exhibits broken strips, intermittent falling, intermittent wall adhesion, sudden narrowing of a single flow, or abrupt changes in surface roughness within the verification window. When using a weight sensor, the continuity of discharge can be indicated by whether the rate of weight increase per unit time is continuous and whether the fluctuation is stable. When using a photoelectric detector, the integrity of the material flow can be reflected by the frequency, duration, and proportion of continuous obstruction. When using a vibration response module of the receiving trough, the stability of the first wave of material can be determined by whether the impact rhythm of the material flow is uniform. A low discharge continuity parameter usually corresponds to areas within the material that are not sufficiently wetted or insufficient initial water addition, manifesting as short-term interruptions in the material flow, incomplete boundaries, or fluctuating falling rhythms. When the discharge continuity parameter meets the set standard, the first wave of material typically exhibits continuous flow, uniform cross-section, and relatively complete boundaries. The advantage of the discharge continuity parameter is that it can quickly identify the overall state of the first wave of material in the window. It is especially suitable for forming a joint judgment condition with humidity value and load signal, so that the secondary water replenishment trigger logic is based on the comprehensive basis of "moisture state + mechanical state + discharge state".

[0071] The optimal parameters for the first wave of material are not used in isolation, but rather in a preset combination for judgment. Preferably, the moisture content at the discharge end and the flow expansion value of the first wave of material can be combined as a moisture content appearance judgment group, the current fluctuation value of the stirring motor and the change value of the stirring torque can be combined as a load resistance judgment group, and the discharge continuity parameter can be used as a comprehensive release check parameter. When both the moisture content appearance judgment group and the load resistance judgment group are below the target range, and the discharge continuity parameter does not meet the set standard, the control component determines that the first wave of material in the current batch is clearly dry. When the moisture content appearance judgment group is within the target range, the load resistance judgment group is slightly high, and the discharge continuity parameter is close to the standard, the system can choose to continue stirring or perform a small secondary water replenishment according to the preset strategy. When all the above parameters are within the target range, the first stirring is determined to have met the requirements for the first wave of material. By setting the first wave material status parameters to one or more of the following: discharge end humidity value, stirring motor current fluctuation value, stirring torque change value, first wave material flow expansion value, and discharge continuity parameters, the first wave material verification can be adapted to different equipment configuration conditions and can also establish single-parameter, dual-parameter, or multi-parameter joint judgment modes according to the actual production line requirements. This ensures that the entire online moisture content detection and stable stirring control method maintains good executability in different implementation scenarios.

[0072] Specifically, in step S5, secondary water replenishment is performed only when the state parameters of the first wave of material are lower than the preset target range, and stirring continues after the secondary water replenishment; when the state parameters of the first wave of material are within the preset target range, secondary water replenishment is not performed and stirring continues directly until the preset stable endpoint is reached.

[0073] The initial batch of mortar exhibits abnormal characteristics within the verification window, such as insufficient water, inadequate slurry film, high internal resistance, or decreased flow continuity. Alternatively, multiple parameters, after joint evaluation, may be below the target level. After reading the parameters within the verification window, the control component typically normalizes each parameter before comparing it to the pre-stored upper and lower limits of the target range. If at least one primary parameter falls below the corresponding lower limit, or multiple secondary parameters deviate from the target range, a secondary water replenishment command is output. If all parameters fall within the target range, or if individual parameters fluctuate slightly but the overall joint evaluation remains within acceptable limits, secondary water replenishment is not performed; instead, the current water level is maintained, and the mixing process continues. With this triggering logic, secondary water replenishment is no longer a fixed step for each batch but an optional step for conditionally correcting the initial water addition. This ensures that each batch of mortar first establishes a basic state based on the initial wet sand moisture content detection and the planned initial water addition, and then the initial batch verification determines whether further correction is needed.

[0074] When the initial material's state parameters are below the preset target range, secondary water replenishment is preferably triggered in stages based on the degree of water shortage and deviation. When the discharge end humidity value is below the lower limit and the initial material flow expansion value is small, while the stirring motor current fluctuation value or stirring torque change value is higher than the corresponding reference range, the control component preferably determines it as a significantly dry state and performs a higher level of secondary water replenishment within the reserved correction water volume range. When only a few parameters slightly deviate from the target range, such as a slightly lower discharge continuity parameter, a slightly smaller flow expansion value, and a humidity value still close to the target lower limit, the control component preferably determines it as a slightly dry state and performs a lower level of secondary water replenishment, or performs short-term continued stirring and then checks the state parameters again. When the discharge end humidity value, flow expansion value, and discharge continuity parameter are all within the target range, and the stirring motor current fluctuation value or torque change value is only slightly higher for a short time, the control component preferably first determines it as insufficient local homogenization and does not immediately trigger secondary water replenishment to avoid misjudging short-term mechanical load fluctuations as true water shortage. By mapping the status parameters of the first batch of material to the trigger logic of the second water replenishment, the water replenishment behavior can be based on "only executing when the deviation reaches the trigger condition", reducing unnecessary water replenishment times and maintaining the consistency of water distribution in each batch of material.

[0075] After the secondary water replenishment is triggered, the control component preferably immediately shuts off the discharge rhythm or maintains the discharge at a low speed, ensuring that the replenished water preferentially enters the high-shear zone within the main mixer. Secondary water replenishment can be achieved through a single, short-duration continuous injection or multiple short-pulse injections, with the total replenished water volume never exceeding the pre-reserved correction water volume. Immediately after water replenishment, the mixing phase continues. This continued mixing redistributes the replenished water throughout the material, eliminating any remaining dry areas from the initial mixing and allowing the replenished material to re-establish a continuous slurry film. Continued mixing preferably lasts 8 to 35 seconds. During this process, the control component simultaneously monitors one or more of the following parameters: mixer motor current, torque, internal humidity signal, and discharge continuity parameters, observing the recovery process after the secondary water replenishment. When the current fluctuation gradually decreases, the torque change tends to be stable, the humidity signal inside the machine enters the target range, and the continuous discharge returns to stability after the mixing continues, it indicates that the secondary water replenishment has been effectively absorbed and homogenized. If the mixing continues for the preset upper limit time and still fails to return to the target state, the control component will preferably output an abnormal batch signal and suspend further material discharge to prevent unstable mortar from entering the subsequent use station.

[0076] When the initial batch of material's state parameters are within the preset target range, secondary water replenishment is not performed, and mixing continues directly. At this point, continued mixing does not serve the homogenization function after water replenishment but primarily serves the final stabilization function, further homogenizing the material formed after the first mixing. The duration of continued mixing without triggering secondary water replenishment is preferably shorter than the duration after triggering secondary water replenishment, ideally between 5 and 20 seconds. During this stage, minor residual state differences within the material are further eliminated, the load on the mixing motor gradually stabilizes, and the continuity of discharge remains stable. By adopting the "continue mixing even without water replenishment" method, all batches of mortar undergo a uniform final stabilization process before discharge, avoiding excessive differences in process rhythm caused by some batches continuing mixing after water replenishment while others are discharged directly without water replenishment. With this setting, even if the initial batch of material in a certain batch is already within the target range, short-term continued mixing can still improve the consistency of the entire batch, ensuring that the final discharge state is closer to the batch that reached the stabilization endpoint after triggering water replenishment.

[0077] When the initial material condition parameters are within the preset target range, a combined determination method is preferred to confirm that secondary water replenishment is not performed. Preferably, the discharge end humidity value can be used as the primary moisture content determination parameter, the initial material flow expansion value and discharge continuity parameter as the appearance flow determination parameter, and the stirring motor current fluctuation value and stirring torque change value as the mechanical load determination parameter. When the primary moisture content determination parameter is within the target range, and both the appearance flow determination parameter and the mechanical load determination parameter do not exceed the allowable fluctuation range, the control component determines that the initial material condition is within the preset target range. When the primary moisture content determination parameter is at the edge of the target range, and both the appearance flow determination parameter and the mechanical load determination parameter show good performance, it can also be determined that secondary water replenishment is not performed. When the primary moisture content determination parameter is close to the target range, but both the appearance flow determination parameter and the mechanical load determination parameter show a tendency towards dryness, the secondary water replenishment logic can still be initiated. Using this determination method can avoid accidental triggering of batches that do not require water replenishment due to occasional fluctuations in a single parameter, and can also avoid missing material that is still relatively dry internally due to a temporarily normal humidity value.

[0078] Furthermore, the control component preferably records whether each batch of the first wave of material triggers secondary water replenishment, the actual amount of water replenished, the duration of continued mixing after water replenishment, and whether the final stable quality endpoint is successfully reached during the verification of each batch. It also establishes corresponding data groups for batches that do not trigger water replenishment and those that do. When multiple batches of the first wave of material fall within the target range without requiring water replenishment under the same sand source, same masterbatch formula, and similar wet sand moisture content conditions, the control component can maintain the current planned water replenishment ratio unchanged. When multiple batches trigger secondary water replenishment due to deviations in similar parameters, the control component can make minor pre-corrections to the planned water replenishment, sampling frequency, or first wave material verification threshold in subsequent batches. By applying the control logic of "only performing secondary water replenishment when the state parameters of the first batch of material are lower than the preset target range, and continuing to stir after secondary water replenishment; when the state parameters of the first batch of material are within the preset target range, not performing secondary water replenishment but directly continuing to stir until the preset stable quality endpoint is reached" to continuous production, each batch of mortar can operate under the same basic process framework. At the same time, relying on the condition triggering mechanism to achieve differentiated water volume correction, the entire production line has both the consistency of a fixed process and the adaptability to raw material fluctuations.

[0079] Specifically, the stabilization endpoint in step S6 is determined by at least one of the following methods: when the current fluctuation of the mixing motor is lower than a preset threshold within a continuous preset time period, and / or the humidity signal in the mixer is within a preset target range, and / or the discharge continuity parameter reaches the set standard, the mortar is determined to have reached the stabilization endpoint.

[0080] The stabilization endpoint is set after the initial material verification and secondary water replenishment. It confirms that the entire batch of mortar has transitioned from the initial mixing state, the immediate state within the initial material window, and the corrected state after secondary water replenishment, to a stable state that allows for continuous discharge and direct use. The fluctuation amplitude of the mixing motor current is lower than a preset threshold. Preferably, within a continuous preset duration, at least one of the peak-to-valley difference, standard deviation, root mean square fluctuation value, or rate of change between adjacent sampling points in the motor current signal is lower than the set upper limit. This indicates that the internal tumbling resistance of the material has become more uniform, and local dry cores, local water-rich areas, and large particle agglomeration areas have been significantly reduced. The continuous preset duration is preferably 3 to 15 seconds. Too short a duration may misjudge instantaneous stability as batch-wide stability, while too long a duration will prolong the batch production cycle, causing the equipment to remain in an unnecessary mixing state. The preset threshold is preferably established based on the current baseline of the same master formula under normal sufficient water conditions, and allows for the use of corresponding threshold groups under different wet sand moisture content ranges, different mixing load ranges, and different batch quality grades, ensuring that the stabilization endpoint judgment is consistent with the actual formula and equipment state.

[0081] The humidity signal inside the mixer is preferably acquired by a microwave humidity probe, capacitive humidity probe, or composite dielectric detection probe located on the side wall, above the bottom of the main mixer drum, or outside the main agitation area of ​​the impeller. When using a microwave humidity probe, the probe emits a microwave signal into the material inside the mixer and calculates the humidity signal based on the change in dielectric properties caused by the moisture content in the material. When using a capacitive probe, the current moisture content is indirectly characterized by the change in dielectric response between the probe and the material. The humidity signal inside the mixer being within the preset target range preferably means that the detected value remains between the upper and lower limits of the target range for a continuous preset time period, and its rate of change gradually decreases. This indicates that the added moisture and the initial planned water addition have been redistributed within the entire batch of material, and there is no longer a significant localized uneven moisture content. The target range of the humidity signal inside the mixer is preferably pre-calibrated based on the master formula, the amount of oven-dry sand, the type of wet sand, and the target construction state, and establishes a corresponding relationship with the humidity value at the discharge end during the first wave of material verification. When the internal humidity signal enters the target range, but the current fluctuation is still too large, it is preferable to continue stirring until both meet the requirements at the same time; when the internal humidity signal has not entered the target range but the current fluctuation has decreased, it is preferable to use the internal humidity signal as the basis for continuing stirring, so as to avoid ending stirring too early due to the temporary stabilization of local mechanical load.

[0082] The discharge continuity parameter should meet the set standard, preferably obtained through one or more of the following: an image acquisition unit at the discharge port, a weight change detection unit at the receiving section, a photoelectric obstruction detection unit, or a vibration response detection unit at the guide section. When using an image acquisition unit, it can identify whether the material flow remains continuous within a preset duration, whether the material strip boundary is intact, whether the material flow width is basically constant, and whether there are obvious discontinuities, retractions, or wall adhesion phenomena. When using a weight change detection unit, it can detect whether the weight increase of the receiving section per unit time is continuous and stable, and whether sudden drops, stops, and violent fluctuations in the weight increase curve have disappeared. When using a photoelectric obstruction detection unit, it can statistically analyze the continuous obstruction ratio and duration of the detection beam by the material flow. When using a vibration response detection unit at the guide section, it can reflect whether the material state is smooth by the rhythmic stability of the material flow impacting the guide section. The discharge continuity parameter meeting the set standard preferably means that the material flow remains uninterrupted, unrestricted, and unburdened within a preset duration, and that the instantaneous fluctuations during the receiving process do not exceed the allowable range. Once the discharge continuity parameters reach the set standard, it indicates that the first round of mixing and subsequent corrections have enabled the entire batch of mortar to have a stable discharge capacity, and can maintain a consistent flow state during subsequent conveying, spraying or spreading processes.

[0083] The optimal method for determining the stabilization endpoint is a single-parameter determination, a two-parameter combined determination, or a three-parameter combined determination. When using a single-parameter determination, it is preferable to select one of the following as the primary determination parameter: the fluctuation amplitude of the mixing motor current, the humidity signal inside the mixer, or the discharge continuity parameter, on production lines with simplified equipment configurations or relatively simple target construction conditions. When using a two-parameter combined determination, it is preferable to combine the fluctuation amplitude of the mixing motor current with the humidity signal inside the mixer, or combine the humidity signal inside the mixer with the discharge continuity parameter, so that both internal uniformity and external discharge stability are considered in the judgment. When using a three-parameter combined determination, it is preferable to determine that the entire batch of mortar has reached the stabilization endpoint only after the fluctuation amplitude of the mixing motor current is below a preset threshold, the humidity signal inside the mixer is within a preset target range, and the discharge continuity parameter meets the set standard. The three-parameter combined determination is suitable for production scenarios with high batch consistency requirements, relatively complete equipment configurations, or large fluctuations in wet sand. The two-parameter combined determination is suitable for most continuous production conditions, while the single-parameter determination is suitable for situations where the equipment structure is relatively simple but the operating conditions are relatively stable. By setting different levels of judgment methods, the same control method can be adapted to production lines with different configurations, while maintaining consistency in the judgment logic of the stable quality endpoint.

[0084] During implementation, the stabilization endpoint is preferably defined in conjunction with the minimum and maximum duration of continued mixing. The minimum duration ensures that even batches without additional water after the first round of mixing undergo sufficient end-of-pipe stabilization, while the maximum duration prevents abnormal batches from being unable to recover after prolonged mixing, thus consuming equipment cycle time. Preferably, the minimum duration of continued mixing is 5 to 20 seconds when no secondary water replenishment is performed, and 8 to 35 seconds after secondary water replenishment; the maximum allowable duration of continued mixing in both cases can be set to 30 to 90 seconds. When the minimum duration is reached and the stabilization endpoint determination condition is met, the control component outputs a finished product release command; when the maximum allowable duration of continued mixing is reached but the stabilization endpoint determination condition is not met, the control component preferably outputs an abnormal batch signal and performs one or more of the following actions: delayed discharge, transfer to a remixing station, import into an independent temporary storage tank, or prompt for manual review. By combining the stabilization endpoint with the upper and lower limits of the continued mixing duration, the entire method can maintain both the ability to quickly release normal batches and the ability to intercept abnormal batches.

[0085] Furthermore, the control component preferably stores the following data corresponding to each batch reaching the stable quality endpoint: the amplitude of the stirring motor current fluctuation, the internal humidity signal, the discharge continuity parameters, the duration of continued stirring, whether secondary water replenishment was performed, and the final discharge status. This data is then associated with the real-time moisture content of the wet sand, the baseline amount of oven-dry sand, the planned initial water addition, and the actual secondary water replenishment. During continuous production, when multiple batches of mortar reach the stable quality endpoint within a similar parameter range under the same master formula and similar wet sand moisture content conditions, the control component can use this range as a priority judgment model for subsequent batches. When several consecutive batches require close to the maximum continued stirring time to reach the stable quality endpoint, or when the discharge continuity is still close to the lower limit even after reaching the stable quality endpoint, the control component can make minor adjustments to the initial planned water addition allocation ratio, the initial material verification threshold, or the target internal humidity range. After adopting the above method, the stabilization endpoint is no longer a static, single fixed value, but a stable release standard that gradually converges under the same master formula, the same equipment, and similar wet sand conditions, so that the entire set of automatic mortar proportioning and stabilization mixing control methods can maintain higher consistency and adaptability in long-term operation.

[0086] Example 1 This embodiment utilizes a batch-type mortar production line, which includes a wet sand silo, sampling and testing components, a powder metering silo, a main mixer, a primary water supply component, a secondary water replenishment component, a discharge section, and a control component. The wet sand silo stores limestone manufactured sand. After pre-screening, the wet sand enters the silo. A discharge gate is located at the bottom of the silo, and a sampling tube with an inner diameter of 42 mm is horizontally positioned approximately 260 mm above the gate. The axis of the sampling tube is perpendicular to the natural descent direction of the wet sand. Inside the sampling tube is a reciprocating sampling rod. The front end of the sampling rod forms a 65 ml sampling cavity. When the sampling rod is pushed inward, the sampling cavity extends into the main material flow area within the silo; when the sampling rod is pulled outward, the sampling cavity enters the testing station. A microwave detection unit is installed at the testing station, with the microwave transmitter and receiver located on opposite sides of the sampling cavity. The real-time moisture content of the wet sand is calculated by measuring the attenuation and phase shift of the microwave signal by the sand sample. Before testing, perform a short discharge for 2 seconds to stabilize the material flow at the bottom of the wet sand bin. Then, perform three consecutive sampling tests with an 8-second interval between each test. Take the median value of the three test results as the real-time moisture content of this batch of wet sand.

[0087] In this embodiment, the mortar masterbatch formula, based on an oven-dry datum, comprises the following components by weight: 80 parts fine aggregate, 12.5 parts cement, 3 parts limestone powder, 2 parts fly ash, 0.8 parts hydrated lime, 0.17 parts cellulose ether, 0.022 parts starch ether, and 0.30 parts redispersible latex powder. Assuming a single batch of oven-dry fine aggregate weighs 800 kg, the corresponding amounts are: 125 kg cement, 30 kg limestone powder, 20 kg fly ash, 8 kg hydrated lime, 1.7 kg cellulose ether, 0.22 kg starch ether, and 3.0 kg redispersible latex powder. The target total water consumption is set at 142 kg. The wet sand used is manufactured limestone sand with a fineness modulus of 2.72, a stone powder content of 5.8%, and a mud content of 0.6%. The moisture content of the wet sand obtained from three microwave tests were 5.4%, 5.6%, and 5.5%, respectively. The median value of 5.5% was taken as the real-time moisture content W of this batch of wet sand. The actual amount of wet sand fed was calculated based on the wet basis mass fraction. The value is 800 / (1-0.055), and the calculated result is 846.56 kg; the amount of water carried in by the wet sand. The value is 846.56 × 0.055, resulting in 46.56 kg; the theoretical total amount of water added. The value is 142-46.56, and the calculated result is 95.44 kg. First-round water addition coefficient. If set to 0.86, then the initial planned water addition volume... The weight is 82.08 kg, with a reserve for correction. It weighs 13.36 kg.

[0088] In this batch of production, 846.56 kg of wet sand and the aforementioned powder were simultaneously fed into a horizontal shaft forced mixer with an effective volume of 1.5 cubic meters and a twin-shaft impeller speed set to 65 rpm. The primary water injection component was activated 4 seconds after the material entered the machine. This component consisted of three sets of injection valves arranged along the length of the mixer. The initial planned water injection of 82.08 kg was divided into two stages: 68.00 kg was continuously injected within the first 10 seconds, and the remaining 14.08 kg was injected within the last 8 seconds. The total duration of the first mixing was set to 56 seconds, with a 22-second wetting stage and a 34-second homogenization stage. During the wetting stage, the impeller speed was maintained at 60% of the rated speed, while during the homogenization stage, it increased to 92% of the rated speed. After the first mixing, the mixer motor current gradually decreased from its initial peak of 82 amps to around 63 amps, but some fluctuations remained. Discharge then began, and the first wave of material verification was initiated.

[0089] The verification window for the first wave of material was set from the 4th to the 10th second after the start of discharge, with the cumulative discharge volume accounting for the top 8% of the total discharge volume as the verification condition. A guide channel was installed below the discharge port, and a short-range microwave probe was installed above the front section of the guide channel to collect the humidity value at the discharge end. An image acquisition module was installed on the side of the guide channel to identify the continuity of material flow and the width of the material strips. A current acquisition module was installed at the drive end of the main mixer to record the current fluctuation value of the mixing motor in real time. The detection results within the verification window for the first wave of material showed that the humidity value at the discharge end was slightly lower than the lower limit of the preset target range, the flow expansion value of the first wave of material only reached 93% of the lower limit of the target range, the boundary of the material strips in the guide channel was slightly contracted, and the current fluctuation amplitude of the mixing motor was 7.8 amps, which was higher than the upper limit of the target range of 6.5 amps corresponding to the master formula. The discharge continuity parameter was close to meeting the standard but not completely meeting the standard. Based on this, the control component determined that the first wave of material in this batch was slightly dry and triggered secondary water replenishment.

[0090] In this embodiment, the actual secondary water replenishment volume is set to 5.0 kg, accounting for 3.52% of the target total water consumption, which is less than the reserved correction water volume of 13.36 kg. Secondary water replenishment is achieved through two sets of small-flow fine-tuning nozzles positioned above the high-shear zone of the mixer, with a spray duration of 4 seconds. Immediately after spraying, the mixer enters the continued mixing stage. The continued mixing stage lasts for 16 seconds, with the impeller speed maintained at 88% of the rated speed. During continued mixing, the current fluctuation of the mixing motor gradually decreases from 7.8 A to 4.2 A, the internal microwave humidity signal enters the preset target range and remains stable, and the image recognition results of the guide channel show that the width of the material strip tends to be constant, the material flow boundary is complete, and the discontinuity disappears. After maintaining this for 6 seconds, the control component determines that the stable quality endpoint has been reached and outputs a finished product release command. The final total amount of water added in this batch was 87.08 kg. Combined with the 46.56 kg of water brought in by the wet sand, the total water consumption of the entire batch was 133.64 kg. After the first and second rounds of water replenishment, the actual amount of water entering the system reached the target control state. The mortar output was a continuous and stable material flow. The surface of the material strips in the guide channel was evenly moistened, with no obvious shiny bleeding phenomenon.

[0091] In this embodiment, the finished mortar is used for thin-layer plastering. Three consecutive batches of mortar produced under the same conditions were observed. The duration of continued mixing after the first batch of material triggered secondary water replenishment was between 14 and 18 seconds. The current fluctuation at the stable endpoint was less than 5 amps, and the width fluctuation of the material strip in the guide trough did not exceed 8%. This indicates that by combining microwave detection using a wet sand silo sampling tube, conversion of oven-dry sand, planned water addition in the first round, verification of the first batch of material, and limited secondary water replenishment, a consistent discharge state and mixing endpoint state can be stably obtained when the wet sand moisture content is in the medium-moisture range. The sampling tube structure, detection location, median value method of three samplings, first batch material verification window, and secondary water replenishment ratio used in this embodiment can be adjusted according to equipment specifications, but the main control principle of combining online wet sand detection and first batch material verification remains unchanged.

[0092] Example 2 This embodiment utilizes a continuous mortar production line, which includes a mixed sand wet silo, sampling and testing components, a double-spiral powder metering component, a main mixer, a primary water supply component, a secondary water replenishment component, an in-machine humidity detection component, a discharge section, and a control component. The mixed sand wet silo stores a mixture of river sand and manufactured sand, pre-mixed at a mass ratio of 35:65. After mixing, the fineness modulus is 2.64, the stone powder content is 4.6%, and the mud content is 0.5%. A transverse sampling tube with an inner diameter of 38 mm is installed on the lower side wall of the wet silo. The front end of the sampling tube is connected to the main material flow area within the silo. A pull-out sampling rod and a microwave detection station are installed at the outer end of the sampling tube. The front end of the sampling rod forms a sampling cavity with a volume of 58 ml. After the sampling rod is pulled outwards, a scraper ring removes the surface-adhered wet sand before it enters the detection station for microwave moisture content testing. The testing station uses a dual-frequency microwave detection unit to perform two rapid scans on the sand sample in the sampling chamber. The control component performs a sliding average based on the results of the four most recent tests to obtain the real-time moisture content of the wet sand during the current continuous production period.

[0093] In this embodiment, the mortar masterbatch formula, based on an oven-dry datum, comprises the following components by weight: 79.5 parts fine aggregate, 12.8 parts cement, 2.6 parts limestone powder, 1.8 parts fly ash, 0.9 parts hydrated lime, 0.18 parts cellulose ether, 0.026 parts starch ether, and 0.34 parts redispersible latex powder. Assuming a single batch oven-dry fine aggregate mass of 780 kg, the corresponding amounts added are: 125.66 kg cement, 25.48 kg limestone powder, 17.64 kg fly ash, 8.82 kg hydrated lime, 1.76 kg cellulose ether, 0.25 kg starch ether, and 3.33 kg redispersible latex powder. The target total water consumption is set at 140 kg. Four tests were conducted before continuous production began, with wet sand moisture contents of 4.1%, 4.3%, 4.2%, and 4.2%, respectively. The control component used the sliding average of 4.2% as the real-time wet sand moisture content W for this period. Calculated based on wet basis mass fraction, actual amount of wet sand fed. The value is 780 / (1-0.042), and the calculated result is 814.20 kg; the amount of water carried in by the wet sand. The value is 814.20 × 0.042, and the calculated result is 34.20 kg; the theoretical total amount of water added. The value is 140-34.20, and the calculated result is 105.80 kg. First-round water addition coefficient. If set to 0.84, then the initial planned water addition volume... The weight is 88.87 kg, with a reserve for correction. It weighs 16.93 kg.

[0094] In this embodiment, the main mixer is a horizontal shaft twin-paddle continuous forced mixer with a rated speed of 72 rpm. Three sets of primary water injection valves are installed along the length of the mixer's feed end, and two sets of secondary water supply fine-tuning nozzles are installed near the high-shear zone. An internal microwave humidity probe is installed in the middle and rear section of the mixer's side wall. During continuous production, wet sand and powder are simultaneously fed into the main mixer. The primary water injection component is activated 3 seconds after the start of feeding, and the planned initial water injection of 88.87 kg is completed within 18 seconds, with 73.00 kg injected in the first 12 seconds and 15.87 kg injected in the last 6 seconds. The first mixing process includes a wetting stage and a homogenization stage. The wetting stage lasts 20 seconds at 62% of the rated speed, and the homogenization stage lasts 28 seconds at 95% of the rated speed. The total duration of the first mixing is 48 seconds. After the first stirring is completed, the current of the stirring motor drops from the peak of 79 amps at the beginning of the feeding stage to around 58 amps. The microwave humidity signal inside the machine enters the lower half of the preset target range, indicating that the material has formed a continuous slurry film and entered a verifiable state.

[0095] In this embodiment, the verification window for the first wave of material is set from the 3rd to the 8th second after the start of discharge, with the cumulative discharge amount accounting for the top 6% of the total batch as the verification condition. A short guide channel and a receiving plate are set downstream of the discharge port. An image recognition module is set above the guide channel, a short-range microwave probe is set on the side of the guide channel, and a weight change detection unit is set below the receiving plate. Within the verification window for the first wave of material, the control component reads the humidity value at the discharge end, the flow expansion value of the first wave of material, the discharge continuity parameter, and the current fluctuation value of the stirring motor. The detection results show that the humidity value at the discharge end is in the middle of the preset target range, the natural spreading width of the first wave of material on the receiving plate is 101% of the target reference value, the material strip boundary recognized by the guide channel image is complete, without obvious necking or wall adhesion, the weight growth curve per unit time is continuous and stable, and the current fluctuation amplitude of the stirring motor is 4.6 amps, which is lower than the target upper limit of 5.5 amps corresponding to this master formula. Based on this, the control component determines that the state of the first wave of material in this batch is in the preset target range, does not perform secondary water replenishment, and directly enters the continued stirring stage.

[0096] Since this batch did not trigger secondary water replenishment, the continued mixing stage was only implemented as the final stabilization stage. The continued mixing time was set to 12 seconds, and the impeller speed was maintained at 90% of the rated speed. During the continued mixing process, the microwave humidity signal inside the machine remained within the target range, the fluctuation amplitude of the mixing motor current further decreased to 3.9 amps, the discharge continuity parameters remained stable, the fluctuation of the material flow cross-sectional width in the guide channel did not exceed 5%, and the surface of the first wave of material on the receiving plate was uniformly wetted, without any shiny surface, localized water, or exposed coarse particles. After maintaining this for 5 seconds, the control component determined that the stabilization endpoint had been reached and output a finished product release command. At this time, the actual total amount of water added to this batch was 88.87 kg, without using the reserved correction water volume. The total water consumption of the entire batch of mortar consisted of 34.20 kg of water brought in by wet sand and 88.87 kg of water added at the first time. The production cycle remained stable, and no additional waiting occurred due to the subsequent water replenishment.

[0097] In this embodiment, the finished mortar is used for continuous spraying of thin-layer plastering. Five batches of products with the same formula, source of wet sand, and equipment parameters were continuously observed. Four batches did not trigger secondary water replenishment within the first wave verification window. One batch had its first round of water replenishment automatically adjusted due to a short-term rise in the moisture content of the wet sand to 4.8%, but it still did not trigger water replenishment. The current fluctuation of the mixing motor corresponding to the stable quality endpoint of all five batches was less than 4.8 amps, the humidity signal inside the machine was within the target range, and the output continuity parameters met the set standards. This indicates that when the moisture content of the mixed sand is in the low to medium range and the front-end microwave detection results are stable, the required first wave of material can be obtained by relying only on the conversion of the oven-dry sand and the planned water replenishment in the first round. Subsequent mixing mainly plays a role in stabilizing the final batch, which can maintain high continuous production efficiency and relatively stable batch consistency.

[0098] Example 3 This embodiment utilizes a batch-type mortar production line operating under low-humidity conditions. The production line includes a wet sand silo, a transverse sampling and testing component, a powder metering component, a main mixer, a primary water supply component, a secondary water replenishment component, an in-machine humidity detection component, a discharge section, and a control component. The wet sand silo stores shaped limestone manufactured sand. After pre-screening, the manufactured sand enters the wet sand silo. A sampling tube with an inner diameter of 45 mm is horizontally installed approximately 310 mm above the lower discharge port of the wet sand silo. A pull-out sampling rod is installed at the outer end of the sampling tube, forming a 72 ml sampling cavity at its tip. After being inserted into the main material flow area inside the wet sand silo, the sampling cavity is filled with the wet sand sample for the current period. After being pulled back, the sample enters a fixed testing station. The testing station is equipped with a microwave detection unit and a scraper ring. The scraper ring is used to remove wet sand adhering to the outer surface of the sampling rod, and the microwave detection unit is used to detect the moisture content of the sand sample in the sampling cavity. During the test, the material is discharged briefly for 3 seconds, and then 4 samples are taken continuously with an interval of 6 seconds between each sample. The control component takes the average value of the 4 test results after removing the extreme values ​​as the real-time moisture content of the wet sand in this batch.

[0099] In this embodiment, the mortar masterbatch formula, based on an oven-dry datum, comprises the following components by weight: 81 parts fine aggregate, 13.2 parts cement, 2.8 parts limestone powder, 1.5 parts fly ash, 0.7 parts hydrated lime, 0.16 parts cellulose ether, 0.020 parts starch ether, and 0.28 parts redispersible latex powder. Assuming a single batch of oven-dry fine aggregate weighs 820 kg, the corresponding amounts added are: 133.63 kg cement, 28.35 kg limestone powder, 15.19 kg fly ash, 7.09 kg hydrated lime, 1.62 kg cellulose ether, 0.20 kg starch ether, and 2.83 kg redispersible latex powder. The target total water consumption is set at 145 kg. The wet sand used is manufactured limestone sand with a fineness modulus of 2.86, a stone powder content of 6.2%, and a mud content of 0.7%. The moisture content of the wet sand obtained from four microwave measurements were 3.0%, 3.3%, 3.2%, and 3.2%, respectively. After removing the maximum and minimum values ​​using the control component, the average of the remaining two values ​​was taken, resulting in a real-time moisture content W of 3.2% for this batch of wet sand. Based on the wet basis mass fraction, the actual amount of wet sand fed was... The value is 820 / (1-0.032), and the calculated result is 847.11 kg; the amount of water carried in by the wet sand. The value is 847.11 × 0.032, resulting in 27.11 kg; the theoretical total amount of water added. The value is 145-27.11, and the calculated result is 117.89 kg. First-round water addition coefficient. If set to 0.89, the initial planned water addition volume will be... The weight is 104.92 kg, with a reserve for correction. It weighs 12.97 kg.

[0100] In this embodiment, the main mixer is a twin-shaft forced mixer with an effective volume of 1.8 cubic meters and a rated speed of 68 rpm. The drive end is equipped with a current acquisition module and a torque feedback module, and an internal microwave humidity probe is installed on the side wall of the rear section of the drum. 820 kg of dry sand (converted to 847.11 kg) is fed into the mixer simultaneously with the other powder components. The primary water injection component is activated 3 seconds after input. This component consists of four sets of injection valves distributed along the length of the mixer. The initial planned water injection of 104.92 kg is divided into two stages: 86.00 kg is continuously injected in the first 11 seconds, and the remaining 18.92 kg is injected in the last 9 seconds. The total duration of the first mixing is set to 62 seconds, with a 24-second wetting stage at 58% of the rated speed and a 38-second homogenization stage at 96% of the rated speed. After the first stirring, the stirring motor current dropped from the initial peak of 88 amps to around 67 amps. The torque feedback value was still higher than the reference value for the normal water content of the master formula. The microwave humidity signal inside the machine was located at the lower edge of the target range, indicating that the material had formed a continuous slurry film, but there was still a tendency to be too dry.

[0101] In this embodiment, the verification window for the first wave of material is set from the 5th to the 12th second after the start of discharge, with the cumulative discharge volume accounting for the top 10% of the total discharge volume as the verification condition. A guide channel and a receiving plate are set downstream of the discharge port. An image acquisition module is set above the guide channel, a short-range microwave probe is set in front of the guide channel, and a weight change detection unit is set below the receiving plate. During the verification window for the first wave of material, the control component simultaneously reads the humidity value at the discharge end, the current fluctuation value of the stirring motor, the change value of the stirring torque, the flow expansion value of the first wave of material, and the discharge continuity parameters. The detection results show that the humidity value at the discharge end is lower than the lower limit of the preset target range, the natural spreading width of the first wave of material on the receiving plate only reaches 89% of the target reference value, the image recognition result of the guide channel shows that the boundary of the material strip is narrow and there is a short-term discontinuity at the end, the current fluctuation amplitude of the stirring motor is 9.6 amps, which is higher than the target upper limit of 6.8 amps corresponding to the master formula, the torque change value remains high during the window period, and the weight growth curve of the receiving plate shows short-term fluctuations. Based on this, the control components determined that the first batch of materials was in a significantly dry state, triggering a higher level of secondary water replenishment.

[0102] In this embodiment, the actual secondary water replenishment volume is set to 5.80 kg, accounting for 4.0% of the target total water consumption, which is less than the reserved correction water volume of 12.97 kg. Secondary water replenishment is achieved through two sets of fine-tuning nozzles positioned above the high-shear zone of the main mixer using a short-duration continuous spraying method. The spraying duration is 5 seconds, and the mixing phase continues immediately after spraying. The continuous mixing phase lasts for 22 seconds, with the mixing speed maintained at 94% of the rated speed. During continuous mixing, the current fluctuation of the mixing motor gradually decreases from 9.6 A to 4.9 A, the torque change value returns to the reference range of normal sufficient water condition, the internal microwave humidity signal moves from the lower edge of the target range to the middle of the target range, and the image recognition results of the guide channel show that the width of the material strip has returned to stability, the boundary is complete, and the discontinuity phenomenon has disappeared. The weight growth curve of the receiving plate becomes continuous and smooth. After maintaining this for 7 seconds, the control component determines that the stable quality endpoint has been reached and outputs a finished product release command. At this point, the actual total amount of water added to this batch was 110.72 kg. Combined with the 27.11 kg of water brought in by the wet sand, the entire batch of material reached the target control state, with continuous and stable discharge, uniform surface wetness, and no obvious dry particles exposed.

[0103] In this embodiment, the finished mortar is used for vertical surface stabilization plastering. Three batches of products with the same formula, equipment parameters, and sand source conditions were continuously observed in low-humidity areas. All three batches triggered secondary water replenishment within the first-wave material verification window, with actual secondary water replenishment amounts of 5.60 kg, 5.80 kg, and 5.70 kg, respectively. The continued mixing times were 20 seconds, 22 seconds, and 21 seconds, respectively. The fluctuation amplitude of the mixing motor current corresponding to the stabilization endpoint was less than 5.2 amps, the humidity signal inside the machine entered the target range, and the fluctuation of the material strip width in the guide trough did not exceed 9%. This embodiment shows that when the real-time moisture content of wet sand is in the low-humidity range, the combination of transverse sampling tube microwave detection, dry sand benchmark conversion, a higher proportion of planned water addition in the first round, and limited secondary water replenishment within the first-wave material window can maintain a stable output state and a consistent mixing endpoint state for the low-humidity manufactured sand mortar.

[0104] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for automatic proportioning and stable mixing control of mortar based on online moisture content detection, characterized in that, Includes the following steps: S1. Perform online moisture content detection on the wet sand entering the mixing system to obtain real-time moisture content data of the wet sand; S2. Based on the real-time moisture content data of the wet sand, the amount of wet sand fed is converted into the baseline amount of absolutely dry sand, and the target total water consumption is determined in combination with the preset mortar masterbatch formula. The first round of planned water addition and reserved correction water volume are further calculated. S3. Add water for the first time according to the planned water addition amount, and mix the converted wet sand with the remaining materials in the mortar masterbatch formula for the first time; S4. Collect the state parameters of the first wave of material in the preset first wave material verification window at the beginning of the discharge stage, and compare the state parameters of the first wave of material with the preset target range. S5. When the state parameters of the first wave of material are lower than the preset target range, a limited secondary water replenishment is performed on the mixing system, and mixing continues after the secondary water replenishment; S6. During the continued mixing process, the mortar state is judged to be stable at the endpoint, and the finished mortar is output when the preset stable endpoint is reached.

2. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 1, characterized in that: The mortar masterbatch formula includes cementitious materials, fine aggregates, water-retaining and thickening components, auxiliary anti-slip components, and interface modifying components. The cementitious materials include at least cement and one or more mineral admixtures. The fine aggregates are the basis amount of oven-dry sand converted from wet sand. The water-retaining and thickening components include at least cellulose ethers. The auxiliary anti-slip components include at least starch ethers. The interface modifying components include at least redispersible latex powder.

3. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 2, characterized in that: The mortar masterbatch formula, based on an oven-dry standard, includes the following components in parts by weight: 78-82 parts fine aggregate, 11-14 parts cement, 2-4 parts limestone powder, 1-3 parts fly ash, 0.5-1.2 parts hydrated lime, 0.14-0.20 parts cellulose ether, 0.015-0.035 parts starch ether, and 0.20-0.45 parts redispersible latex powder.

4. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 1, characterized in that: The wet sand is manufactured sand or a mixture of river sand and manufactured sand, and the wet sand meets at least some of the following conditions: fineness modulus is 2.5 to 2.9, stone powder content is 4.0% to 7.5%, mud content is not higher than 1.2%, and the online detection moisture content working range is 3.0% to 8.5%.

5. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 4, characterized in that: The initial planned water addition and reserved correction water addition mentioned in step S2 are determined based on the difference between the target total water consumption and the water carried in by the wet sand. The water carried in by the wet sand is calculated based on the real-time moisture content data of the wet sand and the amount of wet sand fed. Let the baseline quantity of absolutely dry sand be The real-time moisture content of the wet sand is W, where W is the mass fraction based on the total mass of the wet sand, and the target total water consumption is... , The actual amount of wet sand fed for: ; Water carried in by wet sand for: ; Theoretical total additional water for: ; First round of planned water addition for: ; Reserved correction water volume for: ; in, This is the water addition coefficient for the first round, and .

6. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 5, characterized in that: The first planned water addition in step S3 Theoretical total additional water 82%–90% of the water volume is reserved for correction. Theoretical total additional water 10% to 18%.

7. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 6, characterized in that: The preset first-wave material verification window in step S4 is a preset time interval or preset discharge volume interval after the start of discharge. The actual secondary water replenishment volume in step S5 is not higher than the reserved correction water volume. The preferred total water consumption is... 2% to 4%.

8. The method for automatic proportioning and stable mixing control of mortar based on online moisture content detection according to claim 7, characterized in that: The initial material status parameters in step S4 include one or more of the following: discharge end humidity value, stirring motor current fluctuation value, stirring torque change value, initial material flow expansion value, and discharge continuity parameters.

9. The method for automatic mortar proportioning and stable mixing control based on online moisture content detection according to claim 8, characterized in that: In step S5, secondary water replenishment is performed only when the state parameters of the first wave of material are lower than the preset target range, and stirring continues after secondary water replenishment; when the state parameters of the first wave of material are within the preset target range, secondary water replenishment is not performed and stirring continues directly until the preset stable endpoint is reached.

10. The method for automatic proportioning and stable mixing control of mortar based on online moisture content detection according to claim 9, characterized in that: The stabilization endpoint in step S6 is determined by at least one of the following methods: when the current fluctuation of the mixing motor is lower than the preset threshold within a continuous preset time period, and / or the humidity signal in the mixer is within the preset target range, and / or the discharge continuity parameter reaches the set standard, the mortar is determined to have reached the stabilization endpoint.

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