Construction waste aggregate grading and blending method

Abstract

The application discloses a building waste aggregate grading and blending method, and belongs to the field of building waste resource utilization and recycled aggregate concrete preparation. In order to solve the problems that the source of the recycled aggregate of the building waste is complex, the grading and water absorption and mud content indexes fluctuate, and the water consumption, slump, strength and durability of the concrete are discrete, the application realizes the technical effect of stable control of the concrete preparation parameters under the batch change of the recycled aggregate through batch filing, particle size state detection, confidence interval and water absorption time-varying memory correction, constrained blending and water consumption, cementing material and additive linkage correction.

Description

Technical Field

[0001] This invention relates to the field of resource utilization of construction waste and preparation of recycled aggregate concrete, and particularly to a method for graded and blended construction waste aggregate. Background Technology

[0002] Construction waste, after being crushed and screened, can be used as recycled aggregate in ready-mixed concrete, which helps reduce the consumption of natural aggregates and improve the resource utilization level of construction waste. Due to differences in the source of construction waste, original concrete strength, content of attached mortar, crushing process, and storage conditions, the particle size distribution, water absorption capacity, and fine powder mud content of different batches of recycled aggregate usually fluctuate significantly.

[0003] In current recycled aggregate concrete preparation, mix proportion adjustments are often made based on a fixed replacement rate or single sieving results, which makes it difficult to reflect in a timely manner the gradation deviations between particle size bins, changes in moisture content, and the risk of mud content. When the water absorption rate and current moisture content of recycled aggregate are unstable, directly adding or deducting water based on experience can easily cause deviations in the effective water-cement ratio, leading to accelerated slump loss, insufficient early strength, or dispersion of later durability indicators.

[0004] Meanwhile, simply increasing the mixing water or admixtures alone is insufficient to compensate for the coupled effects of gradation, water absorption, and mud content. Without coordinated control of the compensation amount of cementitious materials and the dynamic addition amount of admixtures, it is easy to cause inconsistencies in the workability and mechanical properties of different batches of concrete. Summary of the Invention

[0005] One objective of this invention is to propose a method for grading and distributing construction waste aggregates. Addressing the problems in existing technologies where the sources of recycled construction waste aggregates are complex, particle size distribution fluctuates, and water absorption and mud content are unstable, leading to discrepancies in water consumption, slump retention, strength, and durability of ready-mixed concrete, this invention proposes a technical solution based on particle size state vectors. This solution combines detection confidence intervals, time-varying water absorption memory values, and a constrained distribution model to determine the feeding ratio, surplus verification, water correction, cementitious material compensation, and dynamic addition of admixtures. This invention achieves the technical effect of stably controlling concrete mix design parameters under batch variations of recycled aggregates.

[0006] This invention provides a method for grading and distributing construction waste aggregates, comprising:

[0007] S1. Establish batch numbers for recycled aggregates from construction waste according to their source, screen them into particle size bins, and collect data from the particle size bins to generate particle size state vectors;

[0008] S2. Generate a detection confidence interval based on the image particle size distribution in the particle size state vector, the water absorption rate and mud content over a specified period, and generate a time-varying memory value for water absorption based on historical moisture content changes, pre-wetting time and slump retention results.

[0009] S3. Establish a constrained distribution model based on the target gradation curve, recycled aggregate replacement rate, design compressive strength level, preset target slump retention time and particle size state vector, and input the detection confidence interval and water absorption time-varying memory value to solve the feeding mass ratio, water compensation required, and three types of margins: gradation safety margin, water absorption compensation margin, and mud content risk margin.

[0010] S4. When all three types of margins are greater than zero, adjust the amount of mixing water added and the amount of delayed water added according to the feeding mass ratio, the amount of water to be compensated and the water absorption compensation margin to obtain the water correction result, and determine the amount of cementitious material compensation according to the mud risk margin and the design compressive strength level.

[0011] S5. When all three types of residuals are greater than zero and the water correction result is executable, output the graded feeding instruction, water deduction or water replenishment instruction, cementitious material compensation instruction and admixture addition instruction according to the feeding mass ratio, water correction result, cementitious material compensation amount and preset target slump holding time; otherwise, output the re-mixing prompt or aggregate batch replacement prompt.

[0012] Optionally, S1 includes:

[0013] The recycled aggregate from the construction waste shall be assigned batch numbers according to the source unit, crushing equipment number, arrival date and intended use of the recycled aggregate;

[0014] The recycled aggregate from construction waste is screened into coarse-grained bins, intermediate-grained bins, and fine-grained bins;

[0015] For each particle size bin, the bin mass, image particle size distribution, proportion of attached mortar, current moisture content, water absorption rate and mud content over a specified period are collected, and the above data are written into the particle size state vector according to the corresponding particle size bin number.

[0016] Optionally, S2 includes:

[0017] Generating the detection confidence interval includes: based on the absolute detection error samples formed by the same detection device in no less than twenty mechanical sieving calibration batches, determining the 95th percentile of the absolute error of the image particle size distribution according to the sieve aperture as the half-width value of the image particle size distribution confidence interval for the corresponding sieve aperture;

[0018] The 95th percentile of the absolute error sample of water absorption rate formed under the same water absorption rate test conditions is used as the half-width value of the confidence interval of water absorption rate for a specified period of time. The specified period of time is the water absorption rate test duration that is pre-written into the test procedure, production formula or design ratio, and is used for the test and calibration of the current batch of samples.

[0019] The 95th percentile of the absolute error sample of mud content formed under the same mud content detection conditions is taken as the half-width value of the mud content confidence interval.

[0020] Furthermore, generating the water absorption time-varying memory value includes: selecting at least five batches of the same particle size silo that have recently completed batching, and obtaining the moisture content upon entering the silo, the moisture content upon exiting the silo, the pre-wetting time, the initial slump after mixing, and the slump when the target slump is maintained for a certain period of time for each batch.

[0021] The change in moisture content is generated based on the difference between the moisture content upon entering the warehouse and the moisture content upon exiting the warehouse. A pre-wetting correction coefficient is generated based on the difference between the pre-wetting time and the pre-wetting time set for the corresponding batch. The pre-wetting time set for the corresponding batch is the pre-wetting time written in the production formula, pre-wetting control record, or blending task record of the corresponding historical batch.

[0022] A slump loss correction coefficient is generated based on the difference between the initial slump after mixing and the slump when the target slump is maintained for a certain time.

[0023] The moisture content change, the pre-wetting correction coefficient, and the slump loss correction coefficient are weighted and corrected according to the decreasing weight of the batch completion time from the nearest to the oldest, to obtain the time-varying memory value of water absorption, and the time-varying memory value of water absorption is used as the input for subsequent calculation of water absorption compensation margin.

[0024] Optionally, S3 includes:

[0025] Establishing the constrained allocation model includes: using the proportion of material feed mass in each particle size bin as the variable to be solved;

[0026] The following constraints are used: the deviation of the mixed gradation curve from the target gradation curve, the mud content obtained by weighting according to the feeding mass ratio, the effective water absorption gap obtained by weighting according to the feeding mass ratio, the recycled aggregate replacement rate, the preset target slump holding time, and the storage balance of each particle size bin. The preset target slump holding time is used as the slump holding constraint or model screening condition. The effective water absorption gap is determined by the upper boundary of the water absorption rate confidence interval for a specified period, the water absorption time-varying memory value, and the current moisture content. The current moisture content is the data collected and written into the particle size state vector. The storage balance is the available balance after deducting the locked feeding amount from the mass in the bin written into the particle size state vector. The locked feeding amount is the feeding amount that was allocated to other batching tasks by the production scheduling record before the start of the current batch and has not yet been released.

[0027] Under the condition of satisfying the design compressive strength level corresponding to the design mix ratio boundary, solve the feeding mass ratio of each particle size bin;

[0028] Furthermore, the mixed gradation curve is obtained by weighting the conservative boundaries of the image particle size distribution confidence interval according to the feeding mass ratio. The conservative boundary is the confidence interval boundary that increases the absolute deviation of each sieve hole relative to the target gradation curve. The gradation safety margin is the first value of the difference between the allowable deviation boundary of each sieve hole gradation and the absolute deviation of the corresponding sieve hole in the mixed gradation curve arranged in ascending order. The allowable deviation boundary of each sieve hole gradation is determined by the allowable deviation range corresponding to the target gradation curve or the design mix ratio boundary.

[0029] The water absorption compensation margin is the difference between the compensable water volume boundary and the required water volume. The required water volume is the total amount obtained by weighting the effective water absorption gap according to the feeding mass ratio. The compensable water volume boundary is derived from the designed mixing water volume, the allowable pre-wetting water volume, and the allowable delayed water addition volume. The allowable pre-wetting water volume and the allowable delayed water addition volume are determined by the designed mix ratio boundary, the allowable addition range of the production equipment, the water-binder ratio control boundary, or the water volume control table pre-written into the production formula.

[0030] The mud content risk margin is the difference between the mud content boundary given by the design mix proportion and the upper boundary of the mud content confidence interval obtained by weighting according to the feed mass ratio.

[0031] Furthermore, the reallocation prompt includes information on the restricted particle size bin set and the reduction of the upper limit of the feeding mass ratio. The upper limit and lower limit of the feeding mass ratio are the variable boundaries of the feeding mass ratio of each particle size bin in the constrained allocation model, and are determined by the storage capacity, the recycled aggregate replacement rate, the design mix ratio boundary and the allowable range of the feeding equipment.

[0032] When no feasible solution is found on the first attempt, a message indicating that the aggregate batch needs to be changed will be output.

[0033] When the gradation safety margin is less than or equal to zero, the gradation contribution value of each particle size bin is calculated for the sieve opening that makes the gradation safety margin less than or equal to zero. The gradation contribution value is the product of the absolute value of the deviation between the conservative boundary of the image particle size distribution information interval of the corresponding particle size bin at that sieve opening and the sieve opening value of the target gradation curve, the directional weight, and the feeding mass ratio. The directional weight is 1 when the deviation direction is consistent with the deviation direction of the mixed gradation curve and 0 when they are inconsistent. When there are multiple sieve openings, they are sorted according to the total value of the gradation contribution value of each sieve opening, and the particle size bin with the first position in the sort is added to the restricted particle size bin set.

[0034] When the water absorption compensation margin is less than or equal to zero, the water absorption contribution value of each particle size bin is calculated. The water absorption contribution value is the product of the effective water absorption gap and the proportion of the feed mass. The particle size bin with the highest water absorption contribution value is added to the restricted particle size bin set.

[0035] When the mud content risk margin is less than or equal to zero, calculate the mud content contribution value of each particle size bin. The mud content contribution value is the product of the upper boundary of the mud content confidence interval and the proportion of feed mass. Add the particle size bin with the highest mud content contribution value to the restricted particle size bin set.

[0036] All granularity bins that rank first in the sorting are added to the restricted granularity bin set;

[0037] In response to the re-adjustment prompt, the upper limit of the feeding mass ratio of each particle size bin in the restricted particle size bin set is reduced by a preset reduction ratio. The preset reduction ratio and the preset re-adjustment number are data pre-written into the adjustment control parameter table, production formula or production scheduling strategy, and the upper limit after the reduction is not less than the lower limit of the feeding mass ratio. The constraint adjustment, water correction, cementitious material compensation and instruction output process are re-executed.

[0038] If no feasible solution is found after re-execution, the preset number of re-adjustments is reached, or the upper limit of any feeding mass ratio reaches the lower limit of the feeding mass ratio, a prompt indicating that the aggregate batch needs to be replaced will be output.

[0039] Optionally, S4 includes:

[0040] The correction of the amount of mixing water added and the amount of delayed water added includes: determining the water volume correction branch based on the effective water absorption gap and the amount of water to be compensated;

[0041] When the required compensation water volume is greater than zero and the water absorption compensation margin is greater than zero, the required compensation water volume is allocated in the order of allowable pre-wetting water volume, adjustable volume of primary mixing water, and allowable delayed water addition volume. The adjustable volume of primary mixing water, the equipment allowable pre-wetting flag, and the equipment support delayed water addition flag are data pre-written into the production equipment parameter table, production formula, or water control table. The pre-wetting water volume is allocated when the current batch is within the allowable start and end time period or allowable duration written in the pre-wetting control record and the equipment allows pre-wetting. The mixing water adjustment volume is allocated when the remaining required compensation water volume does not exceed the adjustable volume of primary mixing water. The delayed water addition volume is allocated when the equipment supports delayed water addition and the remaining required compensation water volume does not exceed the allowable delayed water addition volume. The water absorption compensation margin is used as a constraint that does not exceed the boundary of the compensable water volume.

[0042] If there is still unallocated water that needs to be compensated after the above allocation, a prompt for reallocation or aggregate batch replacement will be issued.

[0043] When the required compensation water is less than or equal to zero, the aggregate surface water is determined based on the portion of the difference between the current moisture content and the saturated surface dry moisture content written into the particle size state vector that is greater than zero. The saturated surface dry moisture content is the data determined by experiment for the corresponding particle size bin or the corresponding batch and written into the particle size state vector or production formula. The amount of water deducted is determined based on the aggregate surface water and the feeding mass ratio to limit additional water from entering the first mixing stage.

[0044] Furthermore, determining the compensation amount of the cementitious material includes: based on the mud risk margin, and combined with the proportion of the attached mortar and the design cementitious material dosage corresponding to the design compressive strength level, determining the compensation amount of at least one compensation material among cement, mineral admixtures, or silica powder, wherein the proportion of the attached mortar is data collected and written into the particle size state vector, and the compensation amount is determined by the design mix proportion boundary, the cementitious material compensation table, or the water-cement ratio control boundary, and after compensation, it satisfies the design mix proportion boundary corresponding to the design compressive strength level.

[0045] Optionally, S5 includes:

[0046] Determining the primary and secondary dosages of the admixture includes: when both the mud content boundary and the compensable water content boundary are positive, dividing the mud content risk margin by the mud content boundary to obtain the mud content margin ratio, and dividing the water absorption compensation margin by the compensable water content boundary to obtain the water absorption margin ratio.

[0047] The mud content risk level and water absorption risk level are determined according to the mud content ratio range and water absorption ratio range in the admixture correction table pre-written into the production formula, respectively. The correction amount corresponding to the first mud content risk level and the first water absorption risk level is greater than that of the second mud content risk level and the second water absorption risk level.

[0048] The admixture correction table is determined by the design mix proportion or admixture compatibility test, and the mud risk level and the water absorption risk level are mapped to the admixture adsorption correction amount and slump retention correction amount;

[0049] The total admixture dosage is obtained by adding the admixture adsorption correction amount, the slump retention correction amount, and the basic admixture dosage. The secondary addition ratio and the secondary addition trigger time are obtained by looking up a table according to the preset target slump retention time. The secondary addition amount is determined according to the total admixture dosage and the secondary addition ratio. The remainder after deducting the secondary addition amount from the total admixture dosage is determined as the primary addition amount.

[0050] The dosage of the basic admixture is the design mix ratio corresponding to the design compressive strength level or the dosage determined by admixture compatibility tests and written into the production formula.

[0051] The beneficial effects of this invention are:

[0052] 1. This invention establishes batch numbers for recycled aggregates from construction waste according to their source and screens them into particle size bins. It collects data such as particle size distribution, moisture content, water absorption rate over a specified period, mud content, and attached mortar to generate a particle size state vector. This allows subsequent blending to be based on the traceable particle size bin state, reducing blending deviations caused by relying solely on experience-based proportions.

[0053] 2. This invention inputs the detection confidence intervals of gradation, water absorption rate and mud content, as well as the time-varying memory value of water absorption, into a constrained blending model, and outputs the feeding mass ratio, gradation safety margin, water absorption compensation margin and mud content risk margin, so that detection errors, short-term water absorption fluctuations and batch differences can be constrained and corrected within the blending model.

[0054] 3. This invention generates instructions for graded feeding, water deduction or replenishment, cementitious material compensation, and dynamic addition of admixtures based on the feeding mass ratio and various surpluses. This can reduce the impact of recycled aggregate gradation fluctuations, unstable water absorption, and mud content risks on slump maintenance, early strength, and durability stability. Attached Figure Description

[0055] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0056] Figure 1 This is a flowchart of a method for grading and allocating aggregates from construction waste.

[0057] Figure 2 This is a flowchart for determining the feasible solution in step S3 of the present invention. Detailed Implementation

[0058] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0059] refer to Figures 1-2 A method for grading and allocating construction waste aggregates, comprising:

[0060] S1. Establish batch numbers for recycled aggregates from construction waste according to their source, screen them into particle size bins, and collect data from the particle size bins to generate particle size state vectors;

[0061] S2. Generate a detection confidence interval based on the image particle size distribution in the particle size state vector, the water absorption rate and mud content over a specified period, and generate a time-varying memory value for water absorption based on historical moisture content changes, pre-wetting time and slump retention results.

[0062] S3. Establish a constrained distribution model based on the target gradation curve, recycled aggregate replacement rate, design compressive strength level, preset target slump retention time and particle size state vector, and input the detection confidence interval and water absorption time-varying memory value to solve the feeding mass ratio, water compensation required, and three types of margins: gradation safety margin, water absorption compensation margin, and mud content risk margin.

[0063] S4. When all three types of margins are greater than zero, adjust the amount of mixing water added and the amount of delayed water added according to the feeding mass ratio, the amount of water to be compensated and the water absorption compensation margin to obtain the water correction result, and determine the amount of cementitious material compensation according to the mud risk margin and the design compressive strength level.

[0064] S5. When all three types of residuals are greater than zero and the water correction result is executable, output the graded feeding instruction, water deduction or water replenishment instruction, cementitious material compensation instruction and admixture addition instruction according to the feeding mass ratio, water correction result, cementitious material compensation amount and preset target slump holding time; otherwise, output the re-mixing prompt or aggregate batch replacement prompt.

[0065] In this specific embodiment, S1 includes:

[0066] Once construction waste recycled aggregate enters the recycled aggregate production line, a batch number is established according to its source. The batch number is generated by splicing the source unit code, crushing equipment number, entry date, and recycled aggregate usage code in a fixed order. Within the same entry date, the same source unit code and the same crushing equipment number are combined with a four-digit serial number to avoid duplicate numbers. The batch number is written into the production database and linked with the entry weighing slip, vehicle number, unloading point, and subsequent particle size bin flow records of that batch to achieve traceability.

[0067] After primary impurity removal, this batch of recycled aggregate enters the multi-layer vibrating screen screening section, with the screen mesh size set sequentially as follows: Aggregates with a diameter of 5mm or less and oversized aggregates with a diameter greater than 31.5mm are returned to the crushing section for further crushing. Aggregates with a diameter between 16mm and 31.5mm enter the coarse aggregate bin, aggregates with a diameter between 5mm and 16mm enter the intermediate aggregate bin, and aggregates with a diameter less than 5mm enter the fine aggregate bin. Each aggregate bin is assigned an independent bin number and is linked to the batch number.

[0068] After each batch of particles is fed into the bin, the bin's internal mass, particle size distribution, proportion of attached mortar, current moisture content, water absorption rate over a specified period, and mud content are collected and solidified. The bin's internal mass is continuously collected by a weighing sensor at the bottom of the bin, with a stable value recorded at the end of the feeding process. The particle size distribution is obtained by capturing continuous images under constant illumination and a fixed shooting distance using an industrial camera installed at the end of the feed conveyor belt. The images are then segmented and converted to equivalent particle sizes according to the sieve aperture sequence.

[0069] ;

[0070] The cumulative pass rate is statistically recorded and stored in association with the grain size bin number. The proportion of attached mortar is obtained by mechanically peeling off samples taken from the grain size bin and comparing the mass difference before and after peeling, and recorded as a mass percentage in the database. The current moisture content is measured by an online microwave moisture meter installed at the discharge port of each grain size bin and recorded as a stable reading after 30 minutes of standing in the bin. The water absorption rate for the specified time period is performed according to the water absorption test duration of 10 minutes, which is consistent with the batch mixing task and is written in the test procedure. It is obtained by dividing the mass difference before and after immersion by the dry mass and recorded. The mud content is determined by the water washing method and recorded as less than [missing value]. The percentage of fine powder mass in the total sample mass is recorded; this information is written as a particle size state vector and can be directly retrieved in subsequent steps, including batch... With granular bins Establish granular state vectors Satisfying the formula:

[0071] ;

[0072] In the formula Indicates batch In granular silos The granular state vector, This represents the batch index and is uniquely identified by the batch number. This represents the grain size bin index, specifying the grain size bin number corresponding to the coarse-grained, intermediate-grained, or fine-grained bin. Indicates granular bin Belongs to batch The internal mass of the warehouse, expressed in kg. The vector represents the particle size distribution in the image, and its components are the cumulative pass rates statistically analyzed according to the above sieve aperture sequence, expressed as a percentage by mass. The proportion of the bonding mortar is expressed as a percentage by mass. This indicates the current moisture content and is expressed as a percentage by mass. The water absorption rate over a specified period is expressed as a percentage by mass. The mud content is expressed as a percentage by mass, and the three types of particle size bins correspond to... The grain size state vector for this batch is constructed by assembling the grain size bins in order from coarse to fine. This vector is then written into the database along with the timestamp, the inspector's number, and the inspector's device number to ensure that the data from the same batch and the same grain size bin can be consistently accessed and traced during subsequent constraint adjustments.

[0073] In this specific embodiment, S2 includes:

[0074] Based on granular state vector Perform the generation of detection confidence intervals and the generation of time-varying water absorption memory values, and write the results into the same batch. With granular bins The state record is used for direct calling by the subsequent constraint allocation model;

[0075] The generation of the detection confidence interval is based on calibration samples formed under the same detection device, algorithm version, and detection conditions. The calibration of the image particle size distribution uses mechanical sieving results as a reference value and compares the cumulative pass rate of each sieve aperture. Twenty consecutively completed mechanical sieving calibration batches are selected, and the calibration of each batch at each sieve aperture is performed. The absolute difference between the cumulative throughput of the image particle size distribution and the cumulative throughput of mechanical sieving is calculated as the absolute detection error sample, and then calculated according to the sieve aperture. The 20 absolute detection error samples were sorted in ascending order, and the 19th sample value was taken as the half-width of the image particle size distribution information interval for that sieve aperture. This allows the image particle size distribution component in the particle size state vector to be... In the sieve holes Expand to The detection confidence interval is determined and its upper or lower bound is allowed to be invoked in subsequent calculations;

[0076] The confidence interval for water absorption rate over a specified time period is determined using error samples formed under the same water absorption rate testing conditions. The specified time period is written into the testing procedure and fixed. For each of the 20 consecutively completed water absorption rate calibration batches, the absolute difference between the water absorption rate test value and the reference value under the same conditions during the specified time period is calculated as the absolute water absorption rate detection error sample. The samples are then sorted in ascending order, and the 19th sample value is taken as the half-width of the confidence interval for water absorption rate during the specified time period. This allows the water absorption rate over a specified time period to be represented in the particle size state vector. Expand to The detection confidence interval;

[0077] The confidence interval for mud content is determined using error samples formed under the same mud content testing conditions. For 20 consecutive mud content calibration batches, the absolute difference between the mud content test value and the reference value measured under the same conditions is calculated as the absolute mud content detection error sample, and the 19th sample value is taken as the half-width of the mud content confidence interval. This will reduce the mud content in the grain-level state vector. Expand to The detection confidence interval, the above and The detection device number and algorithm version remain unchanged and are synchronized with the granular bin number. Binding storage ensures consistency for subsequent batch calls;

[0078] Generation of water absorption time-varying memory values ​​by granular bin Establish separate historical batch queues and select the five most recently completed batches from each particle size silo, categorizing them by completion time from most recent to oldest. For each historical batch, the following data were collected: moisture content upon entering the warehouse, moisture content upon exiting the warehouse, pre-wetting time, initial slump after mixing, and time to maintain the preset target slump. The slump was measured and standardized. The change in moisture content was calculated as the positive value of the difference between the moisture content upon entering and exiting the silo, expressed as a percentage by mass, representing the moisture loss of that particle size silo relative to its entry state within that batch. The pre-wetting correction factor was calculated by dividing the positive value of the difference between the set pre-wetting time and the actual pre-wetting time by the set pre-wetting time and multiplying by 100 to represent the proportion of insufficient pre-wetting. The set pre-wetting time was determined by the production formula or pre-wetting control records of the corresponding historical batch. The slump loss correction factor was calculated by taking the initial slump after mixing and the change in moisture content at time... The portion of the slump difference that is positive is divided by the initial slump after mixing and multiplied by 100 to characterize the slump retention degradation ratio.

[0079] Based on this, using a fixed decreasing weight The granular bin is obtained by weighting the above three types of corrections. Water absorption time-varying memory value It satisfies the formula:

[0080] ;

[0081] In the formula Indicates batch In granular silos The corresponding time-varying water absorption memory value, expressed as a mass percentage, is used as a correction input for the upper boundary of the confidence interval of water absorption rate over a specified period when calculating the effective water absorption gap. Indicates the historical batch number and For the most recently completed batch of ingredients For the furthest batch, Indicates the relationship with historical batch numbers The corresponding time-decreasing weight and satisfy Indicates historical batches In granular silos The change in moisture content is calculated by subtracting the moisture content at the exit of the warehouse from the moisture content at the inlet, and expressing the result as a percentage by mass. Indicates historical batches In granular silos The pre-wetting correction factor is calculated by subtracting the actual pre-wetting time from the set pre-wetting time, and dividing the positive value by the set pre-wetting time, then multiplying by the result. Indicates historical batches The slump loss correction factor is taken and the initial slump after mixing is reduced by the time. The portion of the slump that is positive is divided by the initial slump after mixing, and then multiplied by 100. and After completing the calculation, it is compared with the grain-level state vector. The data is written together into the database and associated with the batch number, granularity bin number, detection device number, algorithm version number, and timestamp to ensure consistent calls to the same data boundary and memory correction in subsequent steps.

[0082] In this specific embodiment, S3 includes:

[0083] In terms of granular state vectors and image particle size distribution information interval half-width value Half-width of the confidence interval for water absorption rate over a specified period Confidence interval half-width of mud content and water absorption time-varying memory value For input, for batch The feeding mass ratios in the three particle size bins (coarse particle size bin, intermediate particle size bin, and fine particle size bin) are calculated separately, and the required compensation water and the three types of surplus are calculated simultaneously.

[0084] The target gradation curve is given by the target gradation curve table and stored in the form of cumulative passing rate for each sieve aperture. The allowable deviation boundaries for each sieve aperture gradation are given and stored by the allowable deviation range of the target gradation curve or the design mix proportion boundary. The recycled aggregate replacement rate is written into and recorded in the production formula. The design mix proportion boundary table corresponding to the design compressive strength level gives the total design aggregate mass for this batch. Design mixing water volume Permissible pre-wetting water volume Permissible delayed water addition and mud content boundary Based on this, the allowable water compensation limit for the current batch is determined. ;

[0085] The remaining storage capacity of each grain size bin is determined by the bin mass in the grain size state vector. Excluding the locked feed quantity allocated by the production scheduling record before the start of the current batch and not yet released. Obtain and record as Based on this, the upper limit of the feed mass ratio is determined. satisfy and This represents the total mass of recycled aggregate fed into the current batch.

[0086] When establishing the constrained allocation model, the feeding mass ratio of each particle size bin is used. As the variable to be solved and fixedly satisfying Based on the actual recycled aggregate feeding quality of each particle size bin As an executable verification quantity and fixedly satisfying The gradation curve after mixing is obtained by weighting the conservative boundaries of the image particle size distribution information interval according to the feed mass ratio, where for each sieve aperture... Compare the cumulative throughput of particle size distribution in the grain size bin images. With target gradation curve The direction of the deviation is determined, and the confidence interval boundary that increases the absolute deviation is selected as the conservative boundary. That is, when Time to take And when Time to take This ensures that the subsequent gradation constraint holds under unfavorable boundary conditions of detection error;

[0087] The effective water absorption gap is determined by the upper boundary of the confidence interval for water absorption rate over a specified time period, the time-varying memory value of water absorption, and the current moisture content, respectively, according to the particle size distribution. The upper boundary of the confidence interval for water absorption rate over a specified time period is taken as... And the current moisture content is taken from the particle size state vector. and will The portion greater than zero is defined as the effective water absorption gap of the particle size bin. This ensures that compensation is only made for gaps that could lead to the absorption of mixing water;

[0088] Mud content constraints are applied to different particle size bins using the upper boundary of the mud content confidence interval. The upper boundary of the mixed mud content is obtained by weighting according to the mass ratio of the feed materials to conservatively constrain the detection error;

[0089] In the solution process, the constrained allocation model uses "minimizing the sum of the absolute values ​​of the deviations of the gradation curves after mixing through each sieve aperture from the target gradation curve" as the objective function. The absolute values ​​of the deviations through each sieve aperture are linearized by introducing non-negative auxiliary variables. Simultaneously, the gradation allowance boundary, storage margin constraint, recycled aggregate replacement rate constraint, mud content boundary constraint, and compensable water content boundary constraint are collectively considered as the feasible region. The simplex method is used to solve the linear programming problem and output the unique feasible solution. and ;

[0090] After obtaining the feed mass ratio, calculate the mixed gradation curve, required water compensation, and three types of margins (grade safety margin, water absorption compensation margin, and mud content risk margin) in one go using the following formula, and record them in the batch record:

[0091] ,

[0092] ,

[0093] ,

[0094] ,

[0095] ;

[0096] In the formula Represents a granular warehouse index and These correspond to coarse-grained bins, intermediate-grained bins, and fine-grained bins, respectively. Indicates the sieve aperture index. This represents the set of sieve aperture indices and is consistent with the sieve aperture sequence in the image particle size distribution vector of step S1. Indicates batch In granular silos The mass ratio of the feed ingredients is dimensionless. This represents the upper limit of the proportion of recycled aggregate input mass, determined jointly by the remaining storage capacity and the total input mass of recycled aggregate, and is dimensionless. This represents the total mass of aggregate determined by the design mix proportion, expressed in kg. This represents the recycled aggregate replacement rate and is dimensionless. Indicates batch The total mass of recycled aggregate fed into the feed, expressed in kg. Indicates batch In granular silos The actual mass of recycled aggregate used, expressed in kg. Indicates granular bin For batch Available storage capacity, in kg. Indicates the target gradation curve at the sieve aperture. The cumulative pass rate, expressed as a percentage of quality. Indicates granular bin In the sieve holes The cumulative pass rate of the image particle size distribution within the conservative boundary of the information interval is expressed as a quality percentage. Indicates batch The gradation curve after mixing is shown in the sieve aperture. The cumulative pass rate, expressed as a percentage of quality. This indicates the gradation curve after mixing relative to the target gradation curve at different sieve openings. The deviation is expressed as a percentage of mass. Indicates sieve aperture The allowable deviation boundaries for gradation are expressed as a percentage by mass. It represents the safety margin for gradation, expressed as a percentage by mass, and is the minimum value of the difference between the absolute value of the allowable deviation boundary and the actual deviation for each sieve aperture. Indicates granular bin The water absorption rate test value within the specified time period is expressed as a percentage by mass. This represents the half-width of the confidence interval for water absorption rate over a specified period, expressed as a percentage by mass. It represents the time-varying memory value of water absorption, expressed as a percentage by mass. This indicates the current moisture content, expressed as a percentage by mass. Indicates the effective water absorption gap and is expressed as a percentage by mass. This indicates the amount of water that needs to be compensated, expressed in kg, and serves as the input for water quantity correction in step S4. This indicates the designed mixing water volume, expressed in kg. Indicates the allowable pre-wetting water volume, expressed in kg. This indicates the allowable amount of water to be added later, expressed in kg. Indicates the compensateable water volume boundary and is expressed in kg. It represents the water absorption compensation margin, expressed in kg, and is the difference between the compensateable water volume boundary and the required compensation water volume. This indicates the mud content measured and expressed as a percentage by mass. This represents the half-width of the confidence interval for mud content, expressed as a percentage by mass. This indicates the mud content boundary given in the design mix proportion and is expressed as a mass percentage. The mud content risk margin is expressed as a percentage by mass and is calculated as the difference between the mud content boundary and the upper boundary of the confidence interval for mixed mud content. This ensures that step S3 outputs the batch size under the condition that the design compressive strength level corresponds to the design mix proportion boundary. Feeding quality ratio Water volume to be compensated and graded safety margin Water absorption compensation margin and mud risk margin .

[0097] In this specific embodiment, S4 includes:

[0098] Safety margin in gradation Water absorption compensation margin and mud risk margin Execute when all values ​​are greater than zero, and in batches. Feeding quality ratio Actual feed quality of recycled aggregate Water volume to be compensated Current moisture content saturated dry moisture content , Adhesive mortar ratio and design compressive strength level The corresponding design mixing water volume and cementitious material boundary are the input generated water volume correction result and cementitious material compensation amount;

[0099] when and The water supply is then introduced into the replenishment branch and distributed in the following order: "allowable pre-wetting water volume, adjustable amount of water for one mixing cycle, and allowable delayed water addition volume". The allowable pre-wetting water volume The amount of water used for mixing can be adjusted. and allowable delayed water addition Pre-written into the water volume control table and in accordance with the design pressure resistance level Binding;

[0100] The equipment pre-wetting permission flag and the equipment delayed water addition support flag are pre-written into the production equipment parameter table, and in this embodiment, both the pre-wetting permission flag and the delayed water addition support flag are in the enabled state.

[0101] The pre-humidification execution conditions are given by the pre-humidification control record, and the pre-humidification control record is written to the batch. The allowed start and end time periods are defined based on the batch start timestamp, and the allowed start and end time duration is defined as 0 min to 15 min. The allocation control program reads the current timestamp and sets the pre-humidification allocation step to be valid when it falls within the allowed start and end time periods; otherwise, the pre-humidification allocation amount is fixed to zero.

[0102] When pre-humidification is effective, first add no more than The amount of water is written as the pre-wetting water volume into the pre-wetting gate setting and is sprayed uniformly before the aggregate enters the mixer. Then, the remaining water to be compensated is kept within a certain limit. The amount of water added during the initial mixing process is incorporated into the initial water metering device, and the remaining unallocated water to be compensated is then added within a range not exceeding [a certain limit]. Within the range, write the delayed water metering device and synchronously write the delayed water trigger condition. If there is still unallocated water that needs to be compensated after the above allocation is completed, it is determined that the water volume correction result is not executable and write the status into the batch record for step S5 to output a re-allocation prompt or aggregate batch replacement prompt.

[0103] when The system then enters the dewatering branch and calculates the dewatering amount based on the aggregate surface moisture content, where the aggregate surface moisture content is defined as the current moisture content. Excess surface dry moisture content The positive difference is weighted according to the actual input quality of recycled aggregate to obtain the batch. Water deduction The water-deducting branch simultaneously fixes the pre-wetting water volume and the delayed water addition volume to zero and sets an additional water replenishment interlock for the first mixing stage to restrict additional water from entering the first mixing stage. The water deduction volume is calculated using the following formula:

[0104] ;

[0105] In the formula Indicates batch The amount of water deducted is calculated in kg. Represents a granular warehouse index and These correspond to coarse-grained bins, intermediate-grained bins, and fine-grained bins, respectively. Indicates batch In granular silos The actual mass of recycled aggregate used, expressed in kg. Indicates granular bin In batch The current moisture content, expressed as a percentage by mass. Indicates granular bin The corresponding saturated surface dry moisture content, expressed as a mass percentage, is determined by testing in that particle size silo and written into the particle size state vector or production formulation. This indicates that the larger of the value in parentheses and zero is taken to ensure that water is deducted only from surface free water;

[0106] After completing the water volume correction, the cementitious material compensation amount is determined, and the cementitious material compensation is based on the mud risk margin. The compensation level is determined by using the main variable and the proportion of adhering mortar, where batch... The proportion of the mixed adhering mortar is determined according to the mass ratio of the feed material for each particle size bin. The weighted summation is used for gear selection, and the cementitious material compensation table is pre-written into the production formula and based on the design compressive strength level. Mud content risk margin The range and the range of mixed-adhesive mortar ratio are indexed to output cement compensation, mineral admixture compensation, and silica fine powder compensation. In this embodiment, the cementitious material compensation table is used for each design compressive strength level. Three risk margin ranges for mud content are set, and the corresponding outputs are a set of defined compensation amounts. The total amount of cementitious material after compensation must not exceed the upper limit of cementitious material given by the design mix proportion boundary, and must not be less than the design amount of cementitious material. At the same time, the compensation materials are selected in the order of "cement first, then mineral admixtures, then siliceous fine powder" and are filled in, and the process is completed before reaching the upper limit of cementitious material to ensure that the design compressive strength level is still met after compensation. The corresponding design mix proportion boundary will ultimately include the amount of initial mixing water, pre-wetting water, delayed water addition, and cementitious material compensation from the water correction results in the batch. The execution instruction buffer is used as the direct input to the output instruction of step S5.

[0107] In this specific embodiment, S5 includes:

[0108] Read the feed mass ratio Actual feed quality of recycled aggregate Graded safety margin Water absorption compensation margin and mud risk margin And read the water volume correction result and the cementitious material compensation amount, when Furthermore, when the water correction result is marked as executable, the graded feeding instruction, water deduction or replenishment instruction, cementitious material compensation instruction, and admixture addition instruction are written into the same batch. The execution instruction buffer is then sent to the production controller;

[0109] Graded feeding instructions are indexed by particle size bins. Write the target feed quality to the key. The feeding control module then converts this into the corresponding cumulative amount on the belt scale and the silo door opening time. These correspond to coarse-grained bins, intermediate-grained bins, and fine-grained bins, and the feeding sequence is fixed as coarse first, then intermediate, then fine. After each grain size bin reaches its limit, the discharge gate of that bin is closed and the belt scale is zeroed to avoid cumulative errors.

[0110] The water deduction or water replenishment command is written by the water control module to the set values ​​of the three metering devices: pre-wetting water volume, primary mixing water adjustment volume, and delayed water addition volume. When the water deduction branch is used, the deduction amount is written to the deduction item of the primary mixing water setting value, and the pre-wetting water volume and delayed water addition volume are both zero, and the additional water replenishment interlock of the primary mixing stage is enabled.

[0111] The cementitious material compensation instruction writes the compensation amounts for cement, mineral admixtures, and silica powder into the target cumulative amounts of the corresponding screw feeders, and the cementitious material metering module performs closed-loop weighing.

[0112] The admixture dosing command maintains the preset target slump for a specified time. For indexing and at mud content boundaries And it can compensate for water volume boundaries The primary and secondary dosages are calculated under the following conditions: the admixture correction table is pre-written into the production formula and a fixed range including the mud content ratio is established. Range of water absorption margin The two are mapped to mud-containing risk level and water absorption risk level, respectively, with the risk levels numbered from high to low as Level 1, Level 2, and Level 3. The admixture correction table outputs the admixture adsorption correction coefficient for the mud-containing risk level. And Level 1, Level 2, and Level 3 are respectively taken Output slump correction coefficient for water absorption risk level And Level 1, Level 2, and Level 3 are respectively taken Dosage of basic admixtures Design compressive strength level The corresponding production formula is given directly, and the total amount of cementitious material in this batch is converted into the batch admixture mass, with the secondary addition ratio. With the trigger time of the second addition By secondary dosing lookup module The production formula obtained through querying and written in this embodiment and corresponding and and will Defined as the trigger time starting from the start of the concrete discharge from the machine, and the main control of the batching plant sends a trigger timestamp to the on-board controller of the transport vehicle so that the second addition can be performed at the time;

[0113] The dosage of the admixture is calculated according to the following formula. After calculation, the first dosage is written into the set value of the admixture metering pump in the mixer, and the second dosage and trigger time are written into the task queue of the admixture metering pump on the transport vehicle.

[0114] ,

[0115] ;

[0116] In the formula It represents the proportion of mud content and is dimensionless. This indicates the margin of risk due to mud content, expressed as a percentage by mass. Indicates the mud content boundary and is expressed as a mass percentage. It represents the percentage of water absorption capacity and is dimensionless. Indicates the water absorption compensation margin, expressed in kg. Indicates the compensateable water volume boundary and is expressed in kg. This represents the adsorption correction factor for the admixture corresponding to the mud-containing risk level, and is dimensionless. This represents the slump correction coefficient corresponding to the water absorption risk level and is dimensionless. Indicates the amount of basic admixtures, expressed in kg. This indicates the adsorption correction amount of the additive, expressed in kg. This indicates the amount of collapse correction, expressed in kg. This indicates the total dosage of the admixture, expressed in kg. This indicates the proportion of a single application and is dimensionless. This indicates the amount to be added twice, expressed in kg. Indicates the dosage per dose, expressed in kg;

[0117] when or or If the water volume correction result is marked as unexecutable, S5 will not issue an execution command but will generate a remixing prompt or aggregate batch change prompt. The remixing prompt will always include the restricted particle size bin set. The information regarding the reduction of the upper limit of the feed mass ratio triggers a re-solution. The restricted particle size bins, determined by their failure type, and the bins ranked first and second in the set are simultaneously added to the set. For all Established sieve aperture Calculate the gradation contribution value of each particle size bin at each sieve aperture, sort them according to the total contribution value of all sieve apertures, and add the one with the largest sum. The contribution value of gradation is determined by the conservative boundary of the particle size distribution information interval in the image of the sieve aperture for that particle size bin. With target gradation curve The absolute value of the deviation, the directional weight, and the proportion of the feed quality The product is multiplied and the directional weight is 1 if the deviation direction of the particle size bin is consistent with the deviation direction after mixing; otherwise, it is 0. Calculate the water absorption contribution value of each particle size bin and sort them according to the water absorption contribution value, then add the bin with the largest water absorption contribution value. Furthermore, the water absorption contribution value is taken as the effective water absorption gap. Ratio of feed weight The product of, when Calculate the mud content contribution value of each particle size bin and sort them by mud content contribution value, then add the bin with the largest mud content contribution value. Furthermore, the contribution value of mud content is taken as the upper boundary of the confidence interval for mud content. Ratio of feed weight The product;

[0118] The information on lowering the upper limit of the feed mass ratio is executed according to the allocation control parameter table, and the preset lowering ratio in this embodiment is [value missing]. And the preset number of readjustments is 3. Each granular bin in the bin sets its variable upper limit. Updated to Simultaneously verify that the updated upper limit is not less than the lower limit of the variable in that granularity bin. Then, steps S3 and S4 are re-executed and the process returns to this step to determine and output instructions.

[0119] When the initial solution is infeasible, or after re-execution there is still no feasible solution, or the preset number of relocation attempts is reached, or any restricted granularity bin appears. When the time comes, S5 outputs an aggregate batch replacement prompt and writes the failure type, restricted particle size bin set, and current batch number in the prompt to guide the production scheduler to replace the recycled aggregate batch and re-file it to enter step S1.

[0120] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0121] This invention introduces the source batch, particle size, detection confidence interval, and water absorption time-varying memory value of recycled aggregate into the same constrained blending process, so that the recycled aggregate from construction waste is detected upon arrival at the site and the mix proportion is corrected, thus providing a unified basis for feeding ratio, water correction, cementitious material compensation, and dynamic addition of admixtures.

[0122] The technical solution of this invention does not merely change empirical parameters, but introduces a detection confidence interval and a time-varying memory value for water absorption into the constrained blending model, and uses the gradation safety margin, water absorption compensation margin, and mud content risk margin as inputs for subsequent control commands, so that the blending process can perform linkage correction for detection errors, changes in water absorption state, and mud content fluctuations.

Claims

1. A method for grading and allocating construction waste aggregates, characterized in that, include: S1. Establish batch numbers for recycled aggregates from construction waste according to their source, screen them into particle size bins, and collect data from the particle size bins to generate particle size state vectors; S2. Generate a detection confidence interval based on the image particle size distribution in the particle size state vector, the water absorption rate and mud content over a specified period, and generate a time-varying memory value for water absorption based on historical moisture content changes, pre-wetting time and slump retention results. S3. Establish a constrained distribution model based on the target gradation curve, recycled aggregate replacement rate, design compressive strength level, preset target slump retention time and particle size state vector, and input the detection confidence interval and water absorption time-varying memory value to solve the feeding mass ratio, water compensation required, and three types of margins: gradation safety margin, water absorption compensation margin, and mud content risk margin. S4. When all three types of margins are greater than zero, adjust the amount of mixing water added and the amount of delayed water added according to the feeding mass ratio, the amount of water to be compensated and the water absorption compensation margin to obtain the water correction result, and determine the amount of cementitious material compensation according to the mud risk margin and the design compressive strength level. S5. When all three types of residuals are greater than zero and the water correction result is executable, output the graded feeding instruction, water deduction or water replenishment instruction, cementitious material compensation instruction and admixture addition instruction according to the feeding mass ratio, water correction result, cementitious material compensation amount and preset target slump holding time; otherwise, output the re-mixing prompt or aggregate batch replacement prompt.

2. The method for grading and allocating construction waste aggregate according to claim 1, characterized in that, S1 includes: The recycled aggregate from the construction waste shall be assigned batch numbers according to the source unit, crushing equipment number, arrival date and intended use of the recycled aggregate; The recycled aggregate from construction waste is screened into coarse-grained bins, intermediate-grained bins, and fine-grained bins. For each bin, the mass, particle size distribution, proportion of attached mortar, current moisture content, water absorption rate over a specified period, and mud content are collected, and the above data are written into the particle size state vector according to the corresponding bin number.

3. The method for grading and allocating construction waste aggregate according to claim 1, characterized in that, Step S2 generates the detection confidence interval by: using absolute detection error samples formed by the same detection device in no less than twenty mechanical sieving calibration batches as a basis, determining the 95th percentile of the absolute error of the image particle size distribution according to the sieve aperture as the half-width value of the image particle size distribution confidence interval for the corresponding sieve aperture; using the 95th percentile of the absolute error sample of water absorption rate formed under the same water absorption rate detection conditions as the half-width value of the water absorption rate confidence interval for a specified time period, wherein the specified time period is the water absorption rate detection duration pre-written into the detection procedure, production formula or design mix ratio, and used for the current batch detection and calibration samples; using the 95th percentile of the absolute error sample of mud content formed under the same mud content detection conditions as the half-width value of the mud content confidence interval.

4. The method for grading and allocating construction waste aggregate according to claim 1, characterized in that, Step S2, generating the time-varying water absorption memory value, includes: selecting at least five batches of the same particle size silo that have recently completed batching; obtaining the inlet moisture content, outlet moisture content, pre-wetting time, initial slump after mixing, and slump at the target slump holding time for each batch; generating a moisture content change based on the difference between the inlet and outlet moisture contents; generating a pre-wetting correction coefficient based on the difference between the pre-wetting time and the pre-wetting time set for the corresponding batch, wherein the pre-wetting time set for the corresponding batch is the set pre-wetting time written in the corresponding historical batch production formula, pre-wetting control record, or blending task record; generating a slump loss correction coefficient based on the difference between the initial slump after mixing and the slump at the target slump holding time; and weighting and correcting the moisture content change, the pre-wetting correction coefficient, and the slump loss correction coefficient according to the decreasing weights of the batch completion times from most recent to oldest, to obtain the time-varying water absorption memory value, and using the time-varying water absorption memory value as input for subsequent calculation of the water absorption compensation margin.

5. The method for grading and allocating construction waste aggregate according to claim 1, characterized in that, Step S3, establishing the constrained allocation model, includes: using the feed mass ratio of each particle size bin as the variable to be solved; using the deviation of the mixed gradation curve from the target gradation curve, the mud content obtained by weighting according to the feed mass ratio, the effective water absorption gap obtained by weighting according to the feed mass ratio, the recycled aggregate replacement rate, the preset target slump retention time, and the storage balance of each particle size bin as the constraint objects; the preset target slump retention time as the slump retention constraint or model screening condition; the effective water absorption gap is determined by the upper boundary of the water absorption rate confidence interval for a specified period, the water absorption time-varying memory value, and the current moisture content; the current moisture content is the data collected and written into the particle size state vector; the storage balance is the available balance after deducting the locked feed amount from the mass in the bin written into the particle size state vector; the locked feed amount is the feed amount allocated to other batching tasks by the production scheduling record before the start of the current allocation batch and has not yet been released; and solving the feed mass ratio of each particle size bin under the condition of satisfying the design mix proportion boundary corresponding to the design compressive strength level.

6. The method for grading and allocating construction waste aggregate according to claim 5, characterized in that, In step S3, the gradation curve after mixing is obtained by weighting the conservative boundaries of the image particle size distribution confidence interval according to the feed mass ratio. The conservative boundaries are the confidence interval boundaries that increase the absolute deviation of each sieve aperture relative to the target gradation curve. The gradation safety margin is the first value of the difference between the allowable deviation boundary of each sieve aperture and the absolute deviation of the corresponding sieve aperture in the mixed gradation curve, arranged in ascending order. The allowable deviation boundary of each sieve aperture is determined by the allowable deviation range corresponding to the target gradation curve or the design mix ratio boundary. The water absorption compensation margin is the difference between the compensateable water volume boundary and the required water volume. The difference between the compensable water amounts, wherein the required compensable water amount is the total amount obtained by weighting the effective water absorption gap according to the feeding mass ratio, and the compensable water amount boundary is derived from the design mixing water amount, the allowable pre-wetting water amount, and the allowable delayed water addition amount, wherein the allowable pre-wetting water amount and the allowable delayed water addition amount are determined by the design mix ratio boundary, the allowable addition range of the production equipment, the water-cement ratio control boundary, or the water amount control table pre-written into the production formula; the mud content risk margin is the difference between the mud content boundary given by the design mix ratio and the upper boundary of the mud content confidence interval obtained by weighting according to the feeding mass ratio.

7. A method for grading and allocating construction waste aggregates according to claim 6, characterized in that, Step S4, correcting the amount of mixing water added and the amount of delayed water addition, includes: determining the water volume correction branch based on the effective water absorption gap and the amount of water to be compensated; when the amount of water to be compensated is greater than zero and the water absorption compensation margin is greater than zero, allocating the amount of water to be compensated in the order of allowable pre-wetting water volume, adjustable amount of mixing water in one batch, and allowable delayed water addition, wherein the adjustable amount of mixing water in one batch, the equipment allowable pre-wetting flag, and the equipment support delayed water addition flag are data pre-written into the production equipment parameter table, production formula, or water volume control table; allocating the pre-wetting water volume when the current batch is within the allowable start and end time period or allowable duration written in the pre-wetting control record and the equipment allows pre-wetting; allocating the mixing water adjustment volume when the remaining amount of water to be compensated does not exceed the adjustable amount of mixing water in one batch; and allocating the mixing water adjustment volume when the remaining amount of water to be compensated does not exceed the adjustable amount of mixing water in one batch. When delayed water addition is supported and the remaining water to be compensated does not exceed the allowable delayed water addition amount, the delayed water addition amount is allocated, and the water absorption compensation margin is used as a constraint not exceeding the boundary of the compensable water amount; if there is still unallocated water to be compensated after the above allocation, a re-mixing prompt or aggregate batch replacement prompt is entered; when the water to be compensated is less than or equal to zero, the aggregate surface water content is determined according to the part greater than zero in the difference between the current moisture content and the saturated surface dry moisture content written in the particle size state vector. The saturated surface dry moisture content is the data determined by the test for the corresponding particle size bin or the corresponding batch and written into the particle size state vector or production formula, and the water deduction amount is determined according to the aggregate surface water content and the feeding mass ratio, restricting additional water addition from entering the first mixing stage.

8. A method for grading and allocating construction waste aggregates according to claim 6, characterized in that, Step S4, determining the compensation amount of the cementitious material, includes: based on the mud risk margin, and combined with the proportion of the adhering mortar and the design cementitious material dosage corresponding to the design compressive strength level, determining the compensation amount of at least one compensation material among cement, mineral admixtures, or silica powder. The proportion of the adhering mortar is data collected and written into the particle size state vector. The compensation amount is determined by the design mix proportion boundary, the cementitious material compensation table, or the water-cement ratio control boundary, and after compensation, it satisfies the design mix proportion boundary corresponding to the design compressive strength level.

9. A method for grading and allocating construction waste aggregates according to claim 6, characterized in that, Step S5, determining the primary and secondary dosages of the admixture, includes: when both the mud content boundary and the compensable water content boundary are positive, dividing the mud content risk margin by the mud content boundary to obtain the mud content margin ratio, and dividing the water absorption compensation margin by the compensable water content boundary to obtain the water absorption margin ratio; determining the mud content risk level and water absorption risk level according to the mud content margin range and water absorption margin range pre-written in the admixture correction table of the production formula, wherein the correction amount corresponding to the first mud content risk level and the first water absorption risk level is greater than that of the second mud content risk level and the second water absorption risk level; the admixture correction table is determined by the design mix proportion or admixture compatibility test. The mud-containing risk level and the water absorption risk level are mapped to admixture adsorption correction amount and slump retention correction amount; the admixture adsorption correction amount, the slump retention correction amount and the basic admixture dosage are added to obtain the total admixture dosage; the secondary addition ratio and the secondary addition trigger time are obtained by looking up the table according to the preset target slump retention time; the secondary addition amount is determined according to the total admixture dosage and the secondary addition ratio; and the remainder after deducting the secondary addition amount from the total admixture dosage is determined as the primary addition amount; the basic admixture dosage is the design mix ratio corresponding to the design compressive strength level or the dosage determined by admixture compatibility test and written into the production formula.

10. A method for grading and allocating construction waste aggregates according to claim 6, characterized in that, The reallocation prompt includes information on the restricted particle size bin set and the reduction of the upper limit of the feed mass ratio. The upper and lower limits of the feed mass ratio are the variable boundaries of the feed mass ratio of each particle size bin in the constrained allocation model, and are determined by the storage margin, recycled aggregate replacement rate, design mix proportion boundary, and allowable range of the feeding equipment. When no feasible solution is found in the initial solution, a prompt indicating that the aggregate batch needs to be changed is output. When the gradation safety margin is less than or equal to zero, the gradation of each particle size bin is calculated for the sieve aperture that makes the gradation safety margin less than or equal to zero. The contribution value is calculated as follows: the absolute value of the deviation between the conservative boundary of the particle size distribution information interval of the corresponding particle size bin at that sieve aperture and the corresponding sieve aperture value of the target gradation curve, the directional weight, and the feed mass ratio. The directional weight is 1 when the deviation direction is consistent with the deviation direction of the mixed gradation curve and 0 when they are inconsistent. When there are multiple sieve apertures, they are sorted according to the total value of the gradation contribution value of each sieve aperture, and the particle size bin with the highest ranking is added to the restricted particle size bin set. When the water absorption compensation margin is less than or equal to zero, the calculation of each particle size bin is performed. The water absorption contribution value, which is the product of the effective water absorption gap and the feed mass ratio, is used to add the grain size bin with the highest water absorption contribution value to the restricted grain size bin set. When the mud content risk margin is less than or equal to zero, the mud content contribution value of each grain size bin is calculated, which is the product of the upper boundary of the mud content confidence interval and the feed mass ratio. The grain size bin with the highest mud content contribution value is added to the restricted grain size bin set. Grain size bins with the same highest mud content contribution value are also added to the restricted grain size bin set. In response to the remixing prompt, the affected grain size bins are added to the restricted grain size bin set. The upper limit of the feed mass ratio of each grain size bin within the limited grain size bin set is reduced according to a preset reduction ratio. The preset reduction ratio and the preset number of re-mixing are data pre-written into the mixing control parameter table, production formula or production scheduling strategy. The upper limit after reduction is not less than the lower limit of the feed mass ratio. The constraint mixing, water correction, cementitious material compensation and instruction output process are re-executed. When there is no feasible solution after re-execution, the preset number of re-mixing is reached, or any upper limit of the feed mass ratio reaches the lower limit of the feed mass ratio, a prompt that the aggregate batch needs to be replaced is output.

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