Concrete pouring method

Abstract

The invention relates to the technical field of building construction, in particular to a concrete pouring method which solves the problems that in the existing concrete pouring process, gas content control depends on manpower, response lags behind, and precision is insufficient. According to the technical scheme, a non-contact ultrasonic gas content monitoring sensor and a pressure sensor are installed at the outlet end of a conveying hose of a concrete pump and a hydraulic system respectively and connected with a controller, and the controller is connected with an air entraining agent metering pump and a defoaming agent metering pump at the same time; the air content and pumping pressure data are monitored in real time, the controller compares the preset range of the air content and calculates the pumping pressure change rate, the adding operation of an air entraining agent or a defoaming agent is automatically triggered, meanwhile, the pumping speed is adjusted, and finally continuous and automatic regulation and control over the air content of concrete are achieved. The method is mainly used in mass concrete pouring construction, the gas content of concrete can be stably controlled, and the construction quality is improved.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, and specifically relates to a concrete pouring method. Background Technology

[0002] In concrete pumping and pouring construction, controlling the air content of concrete is a critical process parameter. Excessive air content leads to decreased concrete strength, while insufficient air content affects its frost resistance and durability. Currently, quality control on construction sites typically involves manual sampling and laboratory testing of air content. However, this method suffers from significant lag, failing to reflect real-time changes in concrete air content during pouring, thus hindering timely adjustments to the mix design.

[0003] On the other hand, concrete pumping pressure fluctuates significantly, often correlated with the workability of concrete, including its air content. However, traditional construction methods do not use pump pressure changes as a real-time reference for air content control. Operators often rely on experience, only attempting to add admixtures to adjust the pressure when they notice a decrease in concrete fluidity or an abnormal increase in pump pressure. This reactive approach lacks foresight and precision.

[0004] Due to the lack of real-time monitoring methods, decisions regarding the addition of air-entraining agents or defoamers are often delayed. Operators cannot accurately determine the timing and amount of addition, frequently resulting in over- or under-addition of additives. This not only affects the stability of concrete quality but also leads to material waste.

[0005] Furthermore, manual control of the addition process makes it difficult to guarantee the timeliness and consistency of the operation. During long-distance, large-volume pouring, there is a significant time delay between the discovery of an anomaly and the execution of the operation, during which the concrete state may have changed significantly, resulting in poor control effects or even adverse effects.

[0006] Attempts to achieve automated control have also encountered difficulties. Firstly, concrete is a mixture, posing challenges to sensor installation and signal acquisition, making it difficult to guarantee the reliability and accuracy of non-contact monitoring. Secondly, the concrete pumping process involves numerous variables, and a single parameter cannot accurately reflect changes in state, requiring coordinated judgment of multiple parameters. Thirdly, the effect of admixture addition is delayed and related to factors such as concrete temperature and pumping speed, making the establishment of timely and effective control logic quite complex.

[0007] Therefore, a control method is needed that can monitor the air content of concrete in real time and automatically respond to abnormal conditions to overcome the lag and inaccuracy of manual control and ensure that the concrete maintains a stable air content during pumping and pouring. Summary of the Invention

[0008] The purpose of this invention is to provide a pouring method that can automatically and in real time control the air content of concrete, so as to improve the quality and efficiency of concrete construction.

[0009] To address the aforementioned problems and achieve the objectives and other advantages of this invention, a concrete pouring method is provided, comprising: Non-contact ultrasonic air content monitoring sensor and pressure sensor are installed at the outlet end of the delivery hose of the concrete pump and on the hydraulic system, respectively. Both the ultrasonic air content monitoring sensor and the pressure sensor are connected to the controller, which is connected to the air-entraining agent metering pump and the defoamer metering pump. When pumping concrete, the ultrasonic air content monitoring sensor and pressure sensor are activated to monitor the air content of the concrete at a frequency of 0.5-2 times / second and the outlet pump pressure of the concrete pump at a frequency of 10-20 times / second, respectively. The controller receives gas content data and pump pressure data, compares the real-time gas content with the preset volume fraction of 4.5-6.0%, and calculates the rate of change of the current pump pressure relative to the reference pump pressure. When the real-time air content remains below 4.5% for 10 seconds and the pump pressure change rate increases positively and exceeds 0.5 MPa / min, the controller starts the air-entraining agent metering pump. The air-entraining agent metering pump adds 1.0-1.5% rosin resin-based air-entraining agent solution at a rate of 50-200 mL / min to the suction end of the concrete pump, and maintains the pumping speed at 90-100% of the initial pumping speed for 90-120 seconds. Then, the addition is stopped and the pumping speed is restored to the initial pumping speed. When the real-time air content remains above 6.0% for 10 seconds, the controller starts the defoamer metering pump. The defoamer metering pump adds 0.5-1.0% (by mass) of organosilicon defoamer solution to the suction end of the concrete pump at a rate of 30-150 mL / min, and reduces the pumping speed to 70-80% of the initial pumping speed. After 90-120 seconds, the addition is stopped and the pumping speed is restored to the initial pumping speed. Repeat the above monitoring, comparison, and control process; Throughout the pumping and pouring process, maintain an ambient temperature of 15-30℃ and a concrete temperature of 10-25℃.

[0010] Preferably, in the concrete pouring method, a bypass with a static mixer is installed in parallel at the suction end of the concrete pump, downstream of the solution addition points of the air-entraining agent metering pump and the defoamer metering pump. The inlet and outlet of the bypass are each connected to the main delivery pipeline via a pneumatic butterfly valve; When the controller starts the air-entraining agent metering pump or the defoamer metering pump, the controller simultaneously opens the pneumatic butterfly valves at the bypass inlet and outlet, allowing the concrete mixture to flow into the bypass and through the static mixer. When neither the air-entraining agent metering pump nor the defoamer metering pump is started, the controller closes the pneumatic butterfly valves at the bypass inlet and outlet, allowing the concrete mixture to pass directly through the main delivery pipeline.

[0011] Preferably, in the concrete pouring method, the air-entraining agent metering pump and the defoamer metering pump are each equipped with a solution heat preservation tank. The solution insulation tank has a built-in temperature sensor and heating and cooling elements; The controller receives concrete temperature data and temperature data inside the solution insulation tank. When it is necessary to add air-entraining agent solution or defoamer solution, the controller activates the heating and cooling elements to adjust the solution temperature to be no more than 5°C different from the concrete temperature before adding it.

[0012] Preferably, in the concrete pouring method, the controller determines that the pump pressure is stable when the fluctuation of the outlet pump pressure value monitored by the pressure sensor does not exceed 0.2 MPa within 60 seconds each time the concrete pump is started and continuously operated at the initial pumping speed. After the pump pressure stabilizes, the controller automatically sets the average pump pressure measured over the next 60 seconds as the initial reference pump pressure. During subsequent pumping, the controller performs a reference pump pressure update operation every 300 seconds: it collects the average pump pressure over a period of 10 seconds. If the absolute value of the deviation between this average value and the current reference pump pressure is less than 0.3 MPa, the controller replaces the current reference pump pressure with this average value. If the real-time gas content remains above 6.0% for 10 seconds or below 4.5% for 10 seconds, the controller will pause the baseline pump pressure update operation.

[0013] Preferably, in the concrete pouring method, after each shutdown of the air-entraining agent metering pump or the defoamer metering pump, the controller initiates a 60-120s delay protection period. During the delay protection period, the controller suspends the monitoring and comparison functions of gas content data and pump pressure change rate; After the delay protection period ends, the controller resumes its function of monitoring and comparing gas content data and pump pressure change rate.

[0014] Preferably, in the concrete pouring method, the controller records the continuous addition time of each start-up of the air-entraining agent metering pump or the defoamer metering pump; When a single continuous addition exceeds 180 seconds, the controller automatically performs a second speed reduction: if defoamer solution is being added, the concrete pump's pumping speed is reduced by 10-15% from 70-80% of the initial pumping speed; if air-entraining agent solution is being added, the concrete pump's pumping speed is reduced by 10-15% from 90-100% of the initial pumping speed. The secondary speed reduction operation continues until 30 seconds after the priming agent metering pump or defoamer metering pump is shut down. After 30 seconds, the concrete pump's pumping speed returned to the speed before this second speed reduction operation.

[0015] Preferably, in the concrete pouring method, after the air-entraining agent metering pump or the defoamer metering pump is started, the controller calculates the real-time rate of change of air content. If the rate of increase in real-time gas content is less than 0.1% / min in volume for 60 seconds when the entraining agent solution is added, the controller will increase the flow rate of the entraining agent solution by 0.5 mL / min. If the rate of decrease in real-time gas content is less than 0.1% / min in volume for 60 seconds after adding defoamer solution, the controller will increase the defoamer solution addition flow rate by 0.5 mL / min. If the rate of increase in real-time gas content is greater than 1.0% / min in volume for 30 seconds when the air-entraining agent solution is added, the controller will reduce the flow rate of the air-entraining agent solution by 0.5 mL / min. If the rate of decrease in real-time gas content is greater than 1.0% / min in volume for 30 seconds when defoamer solution is added, the controller will reduce the defoamer solution addition flow rate by 0.5 mL / min. After the flow rate is adjusted, the controller continues to monitor the real-time rate of change of gas content until it is maintained within the range of 0.2-0.5% / min.

[0016] Preferably, in the concrete pouring method, after the air-entraining agent metering pump or the defoamer metering pump is shut down and the pumping speed is restored to the initial pumping speed, after a 60-120s delay protection period, the controller starts a 60s stable monitoring period. During the stable monitoring period, the controller collects gas content data at a frequency of 0.2 times / s and calculates its range; When the range of air content data during the stable monitoring period exceeds 1.5% by volume, the controller determines that the concrete mixture is in a generally unstable state. The controller sets a continuous pumping speed based on the type of solution previously added: 75-80% of the initial pumping speed if the previously added solution was an antifoaming agent; and 90-95% of the initial pumping speed if the previously added solution was an air-entraining agent. The controller maintains this pumping speed for subsequent operations. In continuous pumping speed operation mode, if the real-time gas content is below 4.5% for 10 seconds and the pump pressure change rate exceeds 0.5 MPa / min, or the real-time gas content is above 6.0% for 10 seconds, the controller will immediately exit the continuous pumping speed operation mode and execute a control process that includes starting the priming agent metering pump or the defoamer metering pump and adjusting the corresponding pumping speed.

[0017] Preferably, in the concrete pouring method, the controller records and counts the total number of times the air-entraining agent metering pump and the defoamer metering pump are started per unit time. When the total number of adjustments exceeds 6 within 5 consecutive minutes, the controller determines that the automatic control system is in a state of frequent operation. The controller automatically and temporarily increases the upper limit of the gas content range of 4.5-6.0% by 0.5-0.8% and temporarily decreases the lower limit by 0.5-0.8%. The controller continuously monitors the adjustment frequency. When the total number of adjustments drops below 3 within 5 consecutive minutes, it automatically restores the gas content range to 4.5-6.0% by volume. During the temporary adjustment of the gas content range, the pumping speed is maintained at 85-90% of the initial pumping speed.

[0018] The present invention has at least the following beneficial effects: This invention achieves real-time, automatic, and precise control of the air content in concrete through the collaborative monitoring of non-contact ultrasonic sensors and pressure sensors, combined with the intelligent decision-making of the controller. It completely solves the problems of response lag and insufficient accuracy in traditional manual control methods, and significantly improves the quality and efficiency of concrete pouring construction.

[0019] This invention introduces pump pressure change rate as a collaborative judgment parameter, which effectively avoids misjudgment and misoperation caused by other factors such as improper slurry-aggregate ratio and material separation. Regulation is only triggered when the gas content is abnormal and the pump pressure change confirms a decrease in pumpability, which greatly improves the accuracy and reliability of system decision-making.

[0020] This invention solves the technical problem of local aggregation and uneven dispersion of additives by setting up a bypass system with a static mixer and automatically opening and closing a pneumatic butterfly valve when adding admixtures, thereby ensuring the uniformity and consistency of air content control.

[0021] This invention, by configuring a solution heat preservation tank for the admixture and achieving coordinated temperature control, ensures that the temperature difference between the admixture solution and the concrete does not exceed 5°C, avoiding problems such as poor admixture dispersion, low efficiency, or component failure caused by temperature mismatch, and improving the system's adaptability and control stability in different environments.

[0022] This invention establishes a dynamic benchmark pump pressure setting and updating mechanism, enabling the system to adapt to changes in pumping conditions. This avoids distortion in the calculation of pump pressure change rate caused by factors such as changes in pipeline resistance, and provides a more accurate and reliable basis for judging gas content control.

[0023] This invention constructs a multi-layered safety protection mechanism by setting a delay protection period and a secondary speed reduction function, which effectively prevents over-regulation, regulation oscillation and abnormal equipment operation, and ensures the stability and durability of the system.

[0024] This invention introduces a feedback adjustment mechanism for the rate of change of air content, which can dynamically adjust the addition flow rate of admixtures, so that the air content tends to the target value at a stable and controllable rate (0.2-0.5% / min), avoiding drastic fluctuations in air content and further improving the control quality and homogeneity of concrete.

[0025] This invention, through a stable state identification and conservative pump speed control strategy, can intelligently determine the state of concrete after the addition of additives and automatically adopt a gentler pumping mode, effectively reducing unnecessary frequent adjustments and promoting the self-stabilization of the concrete state while ensuring construction continuity.

[0026] This invention, by monitoring and regulating the frequency and automatically and temporarily relaxing the gas content control range, endows the system with adaptive capability under abnormal fluctuation conditions, effectively suppresses frequent start-stop of the regulation system, prevents control instability caused by external factors, and enhances the robustness of the system.

[0027] In summary, this invention ultimately achieves fully automatic, high-precision, and highly reliable intelligent control of air content during the pouring of large-volume concrete. It can effectively avoid engineering problems such as pipe blockage and segregation, and ensure the mechanical properties and durability of concrete. It has significant technological advancements and broad engineering application prospects.

[0028] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0029] Figure 1 This is a flowchart of a concrete pouring process according to an embodiment of the present invention. Detailed Implementation

[0030] The present invention will now be described in further detail so that those skilled in the art can implement it based on the description.

[0031] like Figure 1 As shown, the present invention provides a concrete pouring method, comprising: Non-contact ultrasonic air content monitoring sensor and pressure sensor are installed at the outlet end of the delivery hose of the concrete pump and on the hydraulic system, respectively. Both the ultrasonic air content monitoring sensor and the pressure sensor are connected to the controller, which is connected to the air-entraining agent metering pump and the defoamer metering pump. When pumping concrete, the ultrasonic air content monitoring sensor and pressure sensor are activated to monitor the air content of the concrete at a frequency of 0.5-2 times / second and the outlet pump pressure of the concrete pump at a frequency of 10-20 times / second, respectively. The controller receives gas content data and pump pressure data, compares the real-time gas content with the preset volume fraction of 4.5-6.0% (preset gas content), and calculates the rate of change of the current pump pressure relative to the reference pump pressure. When the real-time air content remains below 4.5% for 10 seconds and the pump pressure change rate increases positively and exceeds 0.5 MPa / min, the controller determines that the mixture is viscous, leading to a decrease in pumpability. Subsequently, the air-entraining agent metering pump is started (the defoamer metering pump is turned off). The air-entraining agent metering pump adds a 1.0-1.5% (by mass) rosin resin-based air-entraining agent solution to the concrete pump suction end at a rate of 50-200 mL / min, maintaining the pumping speed at 90-100% of the initial pumping speed for 90-120 seconds. Then, the addition is stopped and the pumping speed is restored to the initial speed. The pump pressure change rate (ΔP / Δt) is defined as the rate of change of the current pump pressure relative to the reference pump pressure. It is obtained by the controller through linear fitting or differential calculation of the pump pressure data collected by the pressure sensor over time. When the calculated result is greater than a positive threshold (e.g., +0.5 MPa / min), it indicates that the pump pressure is increasing and the concrete pumpability is decreasing.

[0032] When the real-time air content remains above 6.0% for 10 seconds, the controller starts the defoamer metering pump (and shuts down the air-entraining agent metering pump). The defoamer metering pump adds 0.5-1.0% (by mass) of organosilicon defoamer solution to the suction end of the concrete pump at a rate of 30-150 mL / min, and reduces the pumping speed to 70-80% of the initial pumping speed. After 90-120 seconds, the addition is stopped and the pumping speed is restored to the initial pumping speed. Repeat the above monitoring, comparison, and control process; Throughout the pumping and pouring process, maintain an ambient temperature of 15-30℃ and a concrete temperature of 10-25℃.

[0033] In the process of concrete pumping and pouring, the control of air content directly affects the pumpability and final molding quality of the concrete. Traditional methods mainly rely on manual experience or single parameter monitoring, such as deciding whether to add air-entraining agents or defoamers based solely on the air content. This single parameter control means that when the monitored air content is below a set lower limit (e.g., 4.5%), the system adds an air-entraining agent; when the monitored air content is above a set upper limit (e.g., 6.0%), the system adds a defoamer. However, poor concrete pumpability is not only caused by abnormal air content, but may also stem from other factors such as improper paste-aggregate ratio and material segregation. Using only air content as the basis for control can easily lead to misjudgment and misoperation.

[0034] In existing technologies, common methods for controlling the air content of concrete mainly rely on manual timed sampling and laboratory testing, which suffer from response lag and the inability to control in real time. Some automated systems have attempted to monitor the air content using a single sensor and automatically trigger the addition of additives, but because they do not consider coordinating parameters such as pump pressure changes, their accuracy and reliability of control remain insufficient. Especially in large-volume or long-distance pumping, pump pressure fluctuations are often closely related to the workability of concrete; ignoring this parameter can easily lead to incorrect timing of control or waste of additives.

[0035] The concrete pouring method provided by this invention achieves synchronous high-frequency monitoring of air content and pump pressure by installing a non-contact ultrasonic air content monitoring sensor at the outlet of the pumping hose and a pressure sensor on the hydraulic system. The controller receives these two types of data, comparing the real-time air content to whether it exceeds the preset range of 4.5% to 6.0%, and also calculates the rate of change of pump pressure relative to a reference value. Only when the air content remains below 4.5% for 10 seconds and the rate of change of pump pressure increases positively and exceeds 0.5 MPa / min is the air-entraining agent addition and speed maintenance strategy initiated; conversely, when the air content remains above 6.0% for 10 seconds, the defoamer addition and speed reduction operation are initiated. The addition operation automatically stops after 90 to 120 seconds, and the pumping speed returns to its initial value. This dual-parameter collaborative judgment mechanism and timed stop strategy significantly improve the accuracy of identifying actual pumping conditions and the controllability of operation, avoiding mis-adjustment caused by other factors.

[0036] This method further enhances the precision of control by employing different pumping speed control strategies when adding different additives. Maintaining the pump speed at 90% to 100% when adding air-entraining agents helps to evenly disperse the air-entraining agents without affecting the continuity of pumping; reducing the speed to 70% to 80% when adding defoamers allows the defoamers to function effectively and avoids the loss of fluidity caused by a sudden drop in air content. The entire process is also carried out within an ambient temperature range of 15℃ to 30℃ and a concrete temperature range of 10℃ to 25℃, ensuring the stability of the basic properties of the concrete materials. Through the above multi-parameter coupling and intelligent decision-making, this method achieves continuous, automatic, and precise control of air content, improving the overall quality and construction efficiency of concrete pouring.

[0037] Example 1 This was implemented in a large-scale foundation slab concrete pouring project. The total volume of concrete for the project was 1200 m³. 3 The pumping distance is 150m horizontally and 35m vertically. The system is equipped with a non-contact ultrasonic gas content monitoring sensor (monitoring frequency 1 time / s) and a pressure sensor (monitoring frequency 15 times / s).

[0038] When the real-time air content remains below 4.5% for 10 seconds and the pump pressure change rate increases positively and exceeds 0.5 MPa / min, the controller determines that the mixture is viscous, resulting in decreased pumpability. Subsequently, the air-entraining agent metering pump is started (the defoamer metering pump is turned off). The air-entraining agent metering pump adds 1.2% rosin resin-based air-entraining agent solution at a mass fraction of 120 mL / min to the suction end of the concrete pump, and the pumping speed is maintained at 95% of the initial pumping speed. After 105 seconds, the addition is stopped and the pumping speed is restored to the initial pumping speed. When the real-time air content remains above 6.0% for 10 seconds, the controller starts the defoamer metering pump (and shuts down the air-entraining agent metering pump). The defoamer metering pump adds 0.7% (by mass) of organosilicon defoamer solution to the suction end of the concrete pump at a rate of 90 mL / min, and reduces the pumping speed to 75% of the initial pumping speed. After 105 seconds, the addition stops and the pumping speed is restored to the initial speed.

[0039] During construction, the ambient temperature is maintained at 20-28℃, and the concrete temperature is controlled at 15-22℃.

[0040] During the entire pouring process, the system triggered 5 additive addition operations, including: 1) At 25 minutes after the pump was started, the gas content was monitored to be below 4.5% for 10 seconds and the pump pressure change rate reached 0.6 MPa / min, triggering the addition of air-entraining agent; 2) At the 48th minute, the gas content was monitored to be above 6.0% for 10 seconds, triggering the addition of defoamer; 3) At the 72nd minute, the gas content was again monitored to be below 4.5% for 10 seconds and the pump pressure change rate reached 0.55 MPa / min, triggering the addition of gas-entraining agent; 4) At the 96th minute, the gas content was monitored to be above 6.0% for 10 seconds, triggering the addition of defoamer; 5) At the 132nd minute, the gas content was monitored to be below 4.5% for 10 seconds and the pump pressure change rate reached 0.65 MPa / min, triggering the addition of air-entraining agent.

[0041] Comparative Example 1 (Single Parameter Control System) In a large-scale foundation slab concrete pouring project, a single-parameter control system was used. The project conditions were exactly the same as in Example 1 (total concrete volume 1200 m³). 3 The pumping distance is 150m horizontally and 35m vertically, with an ambient temperature of 20-28℃ and a concrete temperature of 15-22℃. The system adjusts its operation solely based on air content monitoring data: when the air content is below 4.5%, it automatically adds an air-entraining agent (with the same parameters as in Example 1); when the air content is above 6.0%, it automatically adds an antifoaming agent (with the same parameters as in Example 1), completely ignoring the collaborative judgment of pump pressure change rate.

[0042] During construction, the system triggered 7 additive addition operations after the pump was started, specifically including: At the 18th minute, the gas content was 4.4%, and an air-entraining agent was added (at this time, the pump pressure change rate was only 0.1 MPa / min). At the 35th minute, the gas content was 6.1%, so an antifoaming agent was added. At the 52nd minute, the gas content was 4.3%, and an air-entraining agent was added (at this time, the pump pressure change rate was 0.15 MPa / min). At the 66th minute, the gas content was 6.2%, and defoamer was added. At the 87th minute, the air content was 4.4%, and an air-entraining agent was added (at this time, the pump pressure change rate was 0.05 MPa / min, and due to the fluctuation of the paste-aggregate ratio, this addition actually led to a decrease in the workability of the concrete). At the 104th minute, the gas content was 6.3%, and defoamer was added. At the 126th minute, the gas content was 4.4%, and an air-entraining agent was added.

[0043] During the fifth addition, although the pump pressure did not change significantly, the system still added air-entraining agent because the air content index exceeded the standard, which increased the viscosity of the concrete and caused local pipe blockage. The on-site treatment was interrupted for about 30 minutes.

[0044] Comparative Example 2 (Traditional Manual Control Method) Under the same engineering conditions as in Example 1, a traditional manual control method was used. Samples were manually taken at the pump outlet every 30 minutes and tested using a barometric pressure gas content analyzer. A total of 8 samples were taken throughout the entire construction process. The test results and processing are as follows: At the 30-minute mark, the gas content was measured at 5.5%, which is normal. At the 60th minute, the gas content was measured at 6.5%, which was too high. Based on experience, the operator started adding defoamer at the 65th minute, which lasted for about 2 minutes. At the 90th minute, the gas content was measured at 5.2%, which is normal. At the 120th minute, the gas content was measured at 3.9%, which was low. The operator started adding air-entraining agent at the 128th minute, adding approximately 20% more. At the 150th minute, the gas content was measured at 6.8%, which was significantly high. At this point, slight blockage had occurred due to poor pumpability, and defoamer was added to treat it. At the 180th minute, the gas content was measured at 4.0%, which is low. At the 210th minute, the gas content was measured at 7.0%, which was significantly high, indicating a severe pipe blockage. At the 240th minute, the gas content was measured at 5.8%.

[0045] Due to delayed detection and reliance on experience-based operations, control measures were neither timely nor accurate. Construction was interrupted for a total of 50 minutes due to pipe blockage and other issues.

[0046] Comparative Example 3 (Automated system but with imperfect control logic) The procedure was carried out under the exact same engineering conditions as in Example 1, for pouring a large foundation slab, with a total concrete volume of 1200 m³. 3 The pumping distance is 150m horizontally and 35m vertically. The system configuration is exactly the same as that of Example 1, using a non-contact ultrasonic air content monitoring sensor (monitoring frequency 1 time / s). The ambient temperature during construction is maintained at 20-28℃, the concrete temperature is controlled at 15-22℃, and the preset control target range for air content is also 4.5-6.0%.

[0047] The core difference from Example 1 lies in its control logic: Using only gas content as a single control parameter completely ignores the coordinated judgment of pump pressure change rate; Instead of a fixed duration, the addition time is varied, and the addition is stopped when the gas content reading returns to the normal range.

[0048] Specifically, the system acquires real-time gas content data at a frequency of 1 time per second.

[0049] If the real-time gas content remains above 4.5% for 10 seconds, immediately start the gas-entraining agent metering pump and add the gas-entraining agent (1.2% rosin resin-based gas-entraining agent solution by mass) at a fixed flow rate (120 mL / min).

[0050] If the real-time gas content remains above 6.0% for 10 seconds, immediately start the defoamer metering pump and add defoamer (0.7% by mass defoamer solution) at a fixed flow rate (90 mL / min).

[0051] Otherwise, maintain the current state and do not perform any operation.

[0052] For the addition of air-entraining agent: stop adding the agent when the real-time air content remains above 4.5% for 10 seconds.

[0053] For defoamer addition: stop adding when the real-time air content remains below 6.0% for 10 seconds.

[0054] During construction, as the pumping distance increases, the pipeline friction resistance naturally increases, causing the outlet pump pressure to rise slowly. The system incorrectly associates this normal phenomenon with insufficient gas content. Specifically, when the pump pressure rises slowly, the system detects occasional fluctuations in the gas content reading between 4.4% and 4.5% (still within the normal fluctuation range) and immediately initiates the air-entraining agent addition procedure. Because the stopping condition is that the gas content returns to the normal range, the system continues to add air-entraining agent until the reading exceeds 4.5%, resulting in excessively long single addition times, with one instance even lasting 180 seconds.

[0055] During the crucial two hours of construction, the system experienced five malfunctions: 45 minutes: Gas content 4.4%, start adding air-entraining agent, continue for 150 seconds; 78th minute: Gas content 4.4%, start adding air-entraining agent, continue for 180 seconds; 105th minute: Gas content 4.5%, start adding air-entraining agent, continue for 120 seconds; 132 minutes: Gas content 6.8%, defoamer added, continued for 140 seconds; 156th minute: Gas content 4.2%, start adding air-entraining agent; In summary, the system in Example 1 operates based on a dual-parameter collaborative judgment mechanism (gas content + pump pressure change rate), ensuring a consistently stable pouring process. The gas content fluctuation range remained consistently within the ideal range of 4.6-5.9%, achieving high-precision and stable control. The system triggered five additive addition operations, each with rapid response, accurate timing, and fixed addition duration, without any instances of incorrect addition or over-regulation. The pouring process was continuous and uninterrupted, with no pipe blockage, segregation, or other engineering problems occurring.

[0056] Core sampling after pouring showed that the 28-day compressive strength of the concrete met the standard rate of 100%, with uniform and stable strength values ​​and a dispersion coefficient of only 8%, far superior to conventional control levels. The concrete structure was dense, without harmful cracks, and only had slight local bleeding, which did not affect the overall durability. The results of impermeability and frost resistance tests both met high standard requirements, indicating that the concrete has good durability performance. This Example 1, through real-time, automatic, and precise air content control, significantly improved the quality and efficiency of concrete construction, proving the high reliability and excellent effect of the method of this invention in large-volume concrete pouring.

[0057] Comparative Example 1 employed a single-parameter control system, meaning that under identical engineering conditions, adjustments were made solely based on air content monitoring data, completely ignoring the collaborative judgment of pump pressure change rate. During construction, this system triggered seven additive addition operations. In many of these additions, the pump pressure change rate did not significantly increase (e.g., the pump pressure change rate was only 0.05 MPa / min during the fifth addition), indicating that abnormal air content might be caused by other factors (such as fluctuations in the paste-aggregate ratio) rather than a genuine decrease in pumpability. Consequently, the unnecessary addition of air-entraining agent actually increased concrete viscosity, leading to localized pipe blockage and a construction interruption of approximately 30 minutes. Ultimately, the air content fluctuation range expanded to 4.0-6.5%, and the 28-day compressive strength pass rate was only 91%, with significant strength dispersion. This demonstrates that without pump pressure change rate as a collaborative judgment criterion, the system is susceptible to interference and malfunctions, significantly reducing both control accuracy and concrete quality.

[0058] Comparative Example 2 employed a traditional manual control method, sampling every 30 minutes and using a barometric pressure gas content analyzer for testing. Due to detection lag and experience-based operation, adjustments were extremely untimely and inaccurate. For example, a low gas content (3.9%) was detected at 120 minutes, but air-entraining agent was not added until 128 minutes, and the amount added exceeded 20%; by 150 minutes, a severely high gas content (6.8%) had already caused slight pipe blockage. Construction was interrupted for a total of 50 minutes, with gas content fluctuating between 3.8% and 7.0%, and the 28-day compressive strength pass rate was only 86%, with localized bleeding and unevenness in the structure. This fully exposes the fundamental deficiencies of manual control methods in terms of real-time performance and accuracy.

[0059] Comparative Example 3 employed an automated system, but its control logic was flawed. It relied solely on air content as the single control parameter and used variable addition time (with the stopping condition being the return of air content to the normal range), completely ignoring the collaborative judgment of pump pressure change rate. During construction, the system caused a slow rise in pump pressure due to increased pipeline friction resistance, which was incorrectly associated with insufficient air content. This led to multiple triggerings of air-entraining agent addition within the normal air content fluctuation range (e.g., 4.4-4.5%), with each addition lasting excessively long (once as long as 180 seconds). Five misoperations occurred within the core 2 hours, causing drastic fluctuations in air content between 4.2% and 6.8%, resulting in poor concrete homogeneity. The 28-day compressive strength pass rate was only 88%, with significant differences in core sample strength across different locations. Compared to Comparative Example 1, Comparative Example 3, due to its flawed control logic (variable addition time + lack of pump pressure collaborative judgment), was more prone to over-regulation and drastic fluctuations in air content, thus its final effect was inferior to Comparative Example 1.

[0060] The comparison shows that the dual-parameter collaborative judgment, fixed-duration addition, dynamic benchmark pump pressure update, and multiple protection mechanisms adopted in Example 1 significantly improved the accuracy, stability, and adaptability of the system, ultimately achieving high-precision control of air content and a comprehensive improvement in concrete quality. In contrast, Comparative Examples 1, 2, and 3, due to the lack of pump pressure collaborative judgment, human error, and incomplete logic, all experienced varying degrees of mis-control, construction interruption, or quality degradation, further demonstrating the necessity and superiority of the method proposed in this invention.

[0061] In another embodiment, in the concrete pouring method, a bypass with a static mixer is installed in parallel at the suction end of the concrete pump, downstream of the solution addition points of the air-entraining agent metering pump and the defoamer metering pump. The inlet and outlet of the bypass are each connected to the main delivery pipeline via a pneumatic butterfly valve; When the controller starts the air-entraining agent metering pump or the defoamer metering pump, the controller simultaneously opens the pneumatic butterfly valves at the bypass inlet and outlet, allowing the concrete mixture to flow into the bypass and through the static mixer. When neither the air-entraining agent metering pump nor the defoamer metering pump is started, the controller closes the pneumatic butterfly valves at the bypass inlet and outlet, allowing the concrete mixture to pass directly through the main delivery pipeline.

[0062] During concrete pumping construction, the addition of admixtures often faces the challenge of uneven mixing. Directly injecting air-entraining agents or defoamers into the main delivery pipeline can easily lead to localized aggregation and insufficient dispersion of the additives due to the high flow velocity and complex flow pattern of concrete, affecting the consistency of their effects. Especially under high-flow-rate pumping conditions, uneven mixing may cause lag or fluctuation in the air content control of the concrete, thereby affecting the overall construction quality.

[0063] To address the aforementioned issues, a bypass system with a static mixer is installed in parallel downstream of the additive injection point at the suction end of the concrete pump. The inlet and outlet of this bypass are connected to the main delivery pipeline via pneumatic butterfly valves. When the system starts adding air-entraining agent or defoamer, the controller simultaneously opens the pneumatic butterfly valves at both ends of the bypass, allowing a portion of the concrete mixture to flow into the bypass. As it flows through the static mixer, the additive and concrete achieve thorough and uniform dispersion through the shearing, segmentation, and remixing action of the multi-stage flow-dividing elements within the mixer. After the additive addition is complete, the controller closes the bypass pneumatic butterfly valves, allowing the concrete to flow entirely through the main pipeline, avoiding unnecessary pressure loss.

[0064] This design ensures rapid and uniform mixing of the additive with concrete, significantly improving the response speed and accuracy of air content control. Simultaneously, the parallel arrangement of the bypass system avoids interference with the main fluid delivery, maintaining the continuity of the pumping process. The rapid opening and closing characteristics of the pneumatic butterfly valve ensure that the system can switch flow paths promptly, meeting the needs of real-time control. The use of a static mixer guarantees mixing effectiveness without requiring additional power, demonstrating the practicality and economy of the system design. The entire solution effectively solves the technical challenge of uneven admixture dispersion without excessively increasing system complexity, providing a reliable guarantee for the stable control of concrete quality.

[0065] In another embodiment, the concrete pouring method is provided with a solution heat preservation tank for both the air-entraining agent metering pump and the defoamer metering pump. The solution insulation tank has a built-in temperature sensor and heating and cooling elements; The controller receives concrete temperature data and temperature data inside the solution insulation tank. When it is necessary to add air-entraining agent solution or defoamer solution, the controller activates the heating and cooling elements to adjust the solution temperature to be no more than 5°C different from the concrete temperature before adding it.

[0066] During concrete pumping, the temperature difference between the admixture solution and the concrete mix significantly affects the dispersion and efficiency of the admixture. When the admixture solution is too cold, its viscosity increases, making it difficult to disperse quickly and evenly in the concrete, potentially leading to excessively high local concentrations or incomplete reactions. Conversely, excessively high temperatures may cause some admixture components to decompose or react prematurely, also affecting the effectiveness. This temperature mismatch is particularly pronounced at construction sites where ambient temperatures fluctuate significantly.

[0067] To address this issue, temperature-controlled solution insulated tanks are installed before the metering pumps for both the air-entraining agent and the defoamer. These tanks contain temperature sensors and heating / cooling elements, enabling real-time monitoring and adjustment of the additive solution temperature. The control system simultaneously collects actual concrete temperature data and dynamically initiates heating or cooling operations by comparing the solution temperature with the concrete temperature, ensuring the temperature difference is consistently kept within 5°C before further addition.

[0068] This temperature coordination mechanism effectively ensures the rapid dispersion and full reaction of additives after they enter the concrete, avoiding a decrease in effectiveness or localized performance abnormalities caused by temperature differences. The precise temperature control capabilities of the heating and cooling elements adapt to the construction needs of different seasons and environments, enhancing the system's all-weather applicability. Real-time monitoring by temperature sensors provides a reliable basis for automatic control, ensuring the accuracy and reliability of the regulation process. Without affecting the main process, the entire solution further improves the stability and consistency of air content control through the optimization of this key parameter, providing additional assurance for achieving excellent concrete construction quality.

[0069] In another embodiment, in the concrete pouring method, the controller determines that the pump pressure is stable each time the concrete pump is started and continuously operated at the initial pumping speed. When the fluctuation of the outlet pump pressure value monitored by the pressure sensor does not exceed 0.2 MPa within 60 seconds. After the pump pressure stabilizes, the controller automatically sets the average pump pressure measured over the next 60 seconds as the initial reference pump pressure. During subsequent pumping, the controller performs a reference pump pressure update operation every 300 seconds: it collects the average pump pressure over a period of 10 seconds. If the absolute value of the deviation between this average value and the current reference pump pressure is less than 0.3 MPa, the controller replaces the current reference pump pressure with this average value. If the real-time gas content remains above 6.0% for 10 seconds or below 4.5% for 10 seconds, the controller will pause the baseline pump pressure update operation.

[0070] During concrete pumping, pumping pressure fluctuates due to various factors, including pipe length, number of bends, and changes in concrete mix proportions. These fluctuations make it difficult for a single, fixed pump pressure reference value to accurately reflect actual operating conditions. Using an inaccurate reference pump pressure for calculations can lead to distorted judgments of pump pressure change rates, thereby affecting the accuracy of air content adjustment timing.

[0071] To address this issue, a dynamic reference pump pressure setting and update mechanism was established. At the start of each pumping operation, the system automatically collects pressure data over 60 seconds after the pump pressure stabilizes and sets its average value as the initial reference value. This process ensures the reference value matches the current actual operating conditions. During subsequent pumping operations, the system periodically collects the average pump pressure over 10 seconds. When the deviation between this value and the current reference value is small, the reference value is updated, allowing the reference pump pressure to follow the gradual changes in operating conditions.

[0072] When a persistently abnormal air content is detected, the system pauses the update of the reference pump pressure. This design avoids updating the reference value when the concrete condition is unstable, ensuring the accuracy of the control judgment. Through this dynamic adjustment mechanism, the system can always use a reference value that conforms to the current actual working conditions as a reference to accurately calculate the pump pressure change rate, providing a reliable basis for air content control. The entire solution achieves intelligent management of the reference pump pressure, effectively improving the adaptability and accuracy of the air content control system.

[0073] In another embodiment, in the concrete pouring method, after each shutdown of the air-entraining agent metering pump or the defoamer metering pump, the controller initiates a 60-120s delay protection period. During the delay protection period, the controller suspends the monitoring and comparison functions of gas content data and pump pressure change rate; After the delay protection period ends, the controller resumes its function of monitoring and comparing gas content data and pump pressure change rate.

[0074] In the automatic control of air content in concrete, admixtures require a certain amount of time to fully take effect and be reflected in the monitoring data after addition. This time lag means that for a short period immediately after the additive is turned off, the air content and pump pressure data cannot accurately reflect the control effect. If judgments are made based on these distorted data during this period, the system may misjudge the current state, triggering unnecessary additional additions or reverse operations, resulting in control oscillations.

[0075] To address this issue, the system automatically initiates a 60-120 second delay protection period after each additive addition operation. During this period, the system suspends the monitoring and comparison of gas content data and pump pressure change rate to avoid making incorrect judgments based on distorted data. The delay protection period is set with appropriate duration based on the additive type and its functional characteristics to ensure sufficient time for the additive to fully disperse and exert its effects.

[0076] After the delay protection period ends, the system automatically resumes normal monitoring and comparison functions, continuing to monitor the concrete condition in real time. This mechanism effectively prevents erroneous adjustments caused by asynchrony between data acquisition and the effect of the action, improving the stability and reliability of the system operation. By reasonably setting the protection period, both the accuracy of data acquisition and the appropriateness of the adjustment timing are ensured, enabling the entire control system to more accurately maintain the air content of the concrete within the ideal range.

[0077] In another embodiment, in the concrete pouring method, the controller records the continuous addition time of each start-up of the air-entraining agent metering pump or the defoamer metering pump. When a single continuous addition exceeds 180 seconds, the controller automatically performs a second speed reduction: if defoamer solution is being added, the concrete pump's pumping speed is reduced by 10-15% from 70-80% of the initial pumping speed; if air-entraining agent solution is being added, the concrete pump's pumping speed is reduced by 10-15% from 90-100% of the initial pumping speed. The secondary speed reduction operation continues until 30 seconds after the priming agent metering pump or defoamer metering pump is shut down. After 30 seconds, the concrete pump's pumping speed returned to the speed before this second speed reduction operation.

[0078] During concrete pumping and pouring, when air-entraining agents or defoamers require prolonged addition, high-speed pumping may lead to insufficient mixing between the additives and concrete, affecting the consistency of air content control. When a single addition exceeds 180 seconds, the system automatically performs a secondary speed reduction operation. If defoamer solution is being added, the pumping speed is reduced by 10% to 15% from the current speed; if air-entraining agent solution is being added, the pumping speed is reduced by 10% to 15% from the current speed. This measure extends the residence time of the concrete in the pipeline, promoting more uniform dispersion of the additives in the concrete and avoiding localized uneven concentration or insufficient effect caused by excessive flow rate. The secondary speed reduction continues for 30 seconds after the additive addition is completed, ensuring sufficient time for the additives to complete mixing and reaction. After 30 seconds, the pumping speed returns to the level before the secondary speed reduction, ensuring the control effect while minimizing the impact on the overall construction progress. By dynamically adjusting the pumping speed, this system can maintain the uniformity and stability of the concrete mixture even when adding admixtures for extended periods, improving the reliability of air content control and construction quality.

[0079] In another embodiment, in the concrete pouring method, after the air-entraining agent metering pump or the defoamer metering pump is started, the controller calculates the real-time rate of change of air content. If the rate of increase in real-time gas content is less than 0.1% / min in volume for 60 seconds when the entraining agent solution is added, the controller will increase the flow rate of the entraining agent solution by 0.5 mL / min. If the rate of decrease in real-time gas content is less than 0.1% / min in volume for 60 seconds after adding defoamer solution, the controller will increase the defoamer solution addition flow rate by 0.5 mL / min. If the rate of increase in real-time gas content is greater than 1.0% / min in volume for 30 seconds when the air-entraining agent solution is added, the controller will reduce the flow rate of the air-entraining agent solution by 0.5 mL / min. If the rate of decrease in real-time gas content is greater than 1.0% / min in volume for 30 seconds when defoamer solution is added, the controller will reduce the defoamer solution addition flow rate by 0.5 mL / min. After the flow rate is adjusted, the controller continues to monitor the real-time rate of change of gas content until it is maintained within the range of 0.2-0.5% / min.

[0080] The concrete pouring method provided by this invention further solves the technical problem of inaccurate control caused by inconsistent reaction rates after additive addition. During concrete pumping, relying solely on the absolute value of air content and changes in pump pressure to trigger additive addition may still result in problems of delayed or excessive control response. This is because the actual effect of the additive after addition may deviate from the ideal rate; sometimes the air content changes too slowly, and sometimes it changes too quickly, both of which affect the stability and uniformity of the concrete state.

[0081] Therefore, this method calculates the rate of change in air content in real time after the additive is added. If the rate of increase in air content is below 0.1% / min for 60 seconds after adding the air-entraining agent, it indicates that the air-entraining agent is not effective enough. In this case, the system automatically increases the air-entraining agent flow rate to enhance the effect. Conversely, if the rate of increase in air content is above 1.0% / min for 30 seconds after adding the air-entraining agent, it indicates that the reaction is too fast and may cause drastic fluctuations in air content. In this case, the system reduces the air-entraining agent flow rate to slow down the rate of change. Similarly, when adding defoamer, the flow rate is adjusted according to the rate of decrease in air content to ensure a stable and controllable defoaming process. Through this dynamic flow rate adjustment, the system can make the air content tend towards the target range at a stable rate, avoiding drastic fluctuations in air content and significantly improving the stability of control and the homogeneity of concrete.

[0082] Example 2 Compared to Example 1, a feedback adjustment function based on the rate of change of gas content (including the rate of increase and the rate of decrease) has been added. During the additive addition process, the system calculates the rate of increase or decrease of gas content in real time and dynamically adjusts the addition flow rate. Specifically, during one air-entraining agent addition process, if the system detects that the rate of increase of gas content is below 0.1% / min for 60 seconds, it automatically increases the air-entraining agent addition flow rate from 120 mL / min to 125 mL / min; during another defoamer addition process, if the rate of decrease of gas content is detected to be above 1.0% / min for 30 seconds, it automatically decreases the defoamer addition flow rate from 90 mL / min to 85 mL / min. Through this dynamic adjustment mechanism, the system ensures that the gas content tends towards the target value at a stable rate of 0.2-0.4% / min. During the construction process, the system triggered three additive addition operations, and the gas content fluctuation range was controlled within 4.8-5.5%. After the concrete was poured, the test results showed that the 28-day compressive strength of the concrete met the standard rate of 100%, the strength value of each core sampling point had a dispersion coefficient of only 3%, there was no bleeding segregation, and the structural uniformity was significantly better than that of Example 1.

[0083] The comparative results show that the feedback adjustment function based on the rate of increase / decrease of air content makes the air content control more stable and effectively improves the homogeneity and workability of concrete.

[0084] In another embodiment, in the concrete pouring method, after the air-entraining agent metering pump or the defoamer metering pump is shut down and the pumping speed is restored to the initial pumping speed, after a 60-120s delay protection period, the controller initiates a 60s stable monitoring period. During the stable monitoring period, the controller collects gas content data at a frequency of 0.2 times / s and calculates its range; When the range of air content data during the stable monitoring period exceeds 1.5% by volume, the controller determines that the concrete mixture is in a generally unstable state. The controller sets a continuous pumping speed based on the type of solution previously added: 75-80% of the initial pumping speed if the previously added solution was an antifoaming agent; and 90-95% of the initial pumping speed if the previously added solution was an air-entraining agent. The controller maintains this pumping speed for subsequent operations. In continuous pumping speed operation mode, if the real-time gas content is below 4.5% for 10 seconds and the pump pressure change rate exceeds 0.5 MPa / min, or the real-time gas content is above 6.0% for 10 seconds, the controller will immediately exit the continuous pumping speed operation mode and execute a control process that includes starting the priming agent metering pump or the defoamer metering pump and adjusting the corresponding pumping speed.

[0085] During concrete pumping and pouring, the control of air content is not always achieved in one step. After the additives have taken effect, the state of the concrete mixture may still be in a slightly fluctuating transitional phase. If the system immediately monitors and responds in the conventional mode at this time, it is very easy to cause misjudgments due to temporary data distortion or residual effects, leading to frequent start-ups and shutdowns of the control system, which in turn disrupts the homogeneity of the concrete and the continuity of pumping. This control oscillation not only reduces construction efficiency but may also adversely affect the quality stability of the final formed concrete.

[0086] To address the aforementioned issues, this method does not immediately resume full monitoring after each additive addition and pump speed adjustment operation. Instead, it first enters a preset delay protection period. This phase aims to proactively avoid data instability caused by additive dispersion, reaction, or system inertia, providing sufficient time for the concrete to self-stabilize. After the delay protection period, the system then initiates a dedicated stabilization monitoring period, collecting air content data at a higher frequency and calculating its range to objectively and quantitatively assess the homogeneity and stability of the current concrete mix. If the assessment finds the mix to still be in a generally unstable state, the system automatically switches to a preset, more conservative continuous pumping speed. This speed value is differentiated based on the type of additive added previously, aiming to promote the self-stabilization process of the mix by fine-tuning the fluid transport dynamics without adding admixtures again, thus avoiding over-regulation. However, if the concrete condition clearly deteriorates during this period and exceeds the safety threshold again, the system immediately exits this conservative mode and restarts the complete additive addition and speed adjustment process, ensuring a rapid response to abnormal situations.

[0087] Example 3 This method was implemented in a large bridge pier foundation casting project. Except for the following differences, all other implementation conditions were identical to those in Example 1: After each additive addition operation, a 90-second delay protection period followed by a 60-second stabilization monitoring period was initiated by the controller. During the stabilization monitoring period, the system collected air content data at a frequency of 0.2 times / second and calculated the range. When the range exceeded 1.5%, the concrete was determined to be in a generally unstable state, and a conservative pumping speed was automatically adopted.

[0088] During construction, the system triggered two additive addition operations. The first was initiated after the air content remained above 6.0% for 10 seconds, triggering the defoamer addition program. The second was initiated after the air content remained below 4.5% for 10 seconds and the pump pressure change rate exceeded 0.5 MPa / min, triggering the air-entraining agent addition program. After the second addition operation (air-entraining agent), the air content range measured during the stable monitoring period was 1.6%. The system therefore determined that the concrete was in a generally unstable state and automatically adjusted the pumping speed to 78% of the initial speed for continuous delivery. Under this conservative pumping mode, the concrete state gradually stabilized, and a third additive addition program was not triggered. Throughout the entire pouring process, the air content was ultimately stabilized between 4.7% and 5.8%.

[0089] Tests conducted after pouring showed that the 28-day compressive strength qualification rate of the concrete in Example 3 was 100%, the strength dispersion coefficient was 4%, there was no segregation or bleeding, and the structure was uniform.

[0090] Compared with Example 1, Example 3, by introducing a stable monitoring and conservative pump speed control mechanism, still achieved excellent construction quality with only two addition operations triggered. This effectively proves that the mechanism can reduce unnecessary frequent adjustments and significantly improve the stability of concrete quality while ensuring construction continuity.

[0091] In another embodiment, in the concrete pouring method, the controller records and counts the total number of times the air-entraining agent metering pump and the defoamer metering pump are started per unit time. When the total number of adjustments exceeds 6 within 5 consecutive minutes, the controller determines that the automatic control system is in a state of frequent operation. The controller automatically and temporarily increases the upper limit of the gas content range of 4.5-6.0% by 0.5-0.8% and temporarily decreases the lower limit by 0.5-0.8%. The controller continuously monitors the adjustment frequency. When the total number of adjustments drops below 3 within 5 consecutive minutes, it automatically restores the gas content range to 4.5-6.0% by volume. During the temporary adjustment of the gas content range, the pumping speed is maintained at 85-90% of the initial pumping speed.

[0092] During concrete pumping and pouring, due to fluctuations in material properties or changes in environmental conditions, the automatic control system may frequently initiate the addition of air-entraining agents or defoamers. This frequent adjustment not only exacerbates equipment wear and tear but may also lead to repeated changes in the concrete's state, affecting construction continuity and final molding quality. Frequent addition of admixtures can also cause increased fluctuations in air content, even reducing concrete workability and increasing the risk of pipe blockage.

[0093] To address the aforementioned issues, the system records and tracks the total number of times the gas-inducing agent and defoamer metering pumps are activated per unit time, monitoring the control frequency in real time. When the total number of adjustments exceeds 6 within 5 consecutive minutes, the system determines that it is currently operating frequently and automatically raises the upper limit of the gas content control range by 0.5% to 0.8% and lowers the lower limit by 0.5% to 0.8%. This adjustment effectively reduces unnecessary control actions and alleviates the instability caused by frequent system responses.

[0094] During the temporary relaxation of the air content range, the system continuously monitors the adjustment frequency. When the total number of adjustments within 5 consecutive minutes drops below 3, it indicates that the concrete condition has stabilized, and the system automatically restores the air content range to the original 4.5% to 6.0%. Furthermore, throughout the entire temporary adjustment phase, the pumping speed is maintained at 85% to 90% of the initial pumping speed, ensuring smooth concrete delivery while avoiding new disturbances introduced by speed changes. Through frequency sensing and dynamic tolerance adjustment, the system significantly improves its adaptability and control stability under complex working conditions, ensuring a smooth and efficient concrete pouring process.

[0095] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A concrete pouring method, characterized in that, include: Non-contact ultrasonic air content monitoring sensor and pressure sensor are installed at the outlet end of the delivery hose of the concrete pump and on the hydraulic system, respectively. Both the ultrasonic air content monitoring sensor and the pressure sensor are connected to the controller, which is connected to the air-entraining agent metering pump and the defoamer metering pump. When pumping concrete, the ultrasonic air content monitoring sensor and pressure sensor are activated to monitor the air content of the concrete at a frequency of 0.5-2 times / second and the outlet pump pressure of the concrete pump at a frequency of 10-20 times / second, respectively. The controller receives gas content data and pump pressure data, compares the real-time gas content with the preset volume fraction of 4.5-6.0%, and calculates the rate of change of the current pump pressure relative to the reference pump pressure. When the real-time air content remains below 4.5% for 10 seconds and the pump pressure change rate increases positively and exceeds 0.5 MPa / min, the controller starts the air-entraining agent metering pump. The air-entraining agent metering pump adds 1.0-1.5% rosin resin-based air-entraining agent solution at a rate of 50-200 mL / min to the suction end of the concrete pump, and maintains the pumping speed at 90-100% of the initial pumping speed for 90-120 seconds. Then, the addition is stopped and the pumping speed is restored to the initial pumping speed. When the real-time air content remains above 6.0% for 10 seconds, the controller starts the defoamer metering pump. The defoamer metering pump adds 0.5-1.0% (by mass) of organosilicon defoamer solution to the suction end of the concrete pump at a rate of 30-150 mL / min, and reduces the pumping speed to 70-80% of the initial pumping speed. After 90-120 seconds, the addition is stopped and the pumping speed is restored to the initial pumping speed. Repeat the above monitoring, comparison, and control process; Throughout the pumping and pouring process, maintain an ambient temperature of 15-30℃ and a concrete temperature of 10-25℃.

2. The concrete pouring method as described in claim 1, characterized in that, At the suction end of the concrete pump, downstream of the solution addition points of the air-entraining agent metering pump and the defoamer metering pump, a bypass with a static mixer is installed in parallel. The inlet and outlet of the bypass are each connected to the main delivery pipeline via a pneumatic butterfly valve; When the controller starts the air-entraining agent metering pump or the defoamer metering pump, the controller simultaneously opens the pneumatic butterfly valves at the bypass inlet and outlet, allowing the concrete mixture to flow into the bypass and through the static mixer. When neither the air-entraining agent metering pump nor the defoamer metering pump is started, the controller closes the pneumatic butterfly valves at the bypass inlet and outlet, allowing the concrete mixture to pass directly through the main delivery pipeline.

3. The concrete pouring method as described in claim 1, characterized in that, The air-entraining agent metering pump and the defoamer metering pump are each equipped with a solution heat preservation tank; The solution insulation tank has a built-in temperature sensor and heating and cooling elements; The controller receives concrete temperature data and temperature data inside the solution insulation tank. When it is necessary to add air-entraining agent solution or defoamer solution, the controller activates the heating and cooling elements to adjust the solution temperature to be no more than 5°C different from the concrete temperature before adding it.

4. The concrete pouring method as described in claim 1, characterized in that, The controller determines that the pump pressure is stable when the fluctuation of the outlet pump pressure value monitored by the pressure sensor does not exceed 0.2MPa within 60 seconds each time the concrete pump is started and runs continuously at the initial pumping speed. After the pump pressure stabilizes, the controller automatically sets the average pump pressure measured over the next 60 seconds as the initial reference pump pressure. During subsequent pumping, the controller performs a reference pump pressure update operation every 300 seconds: it collects the average pump pressure over a period of 10 seconds. If the absolute value of the deviation between this average value and the current reference pump pressure is less than 0.3 MPa, the controller replaces the current reference pump pressure with this average value. If the real-time gas content remains above 6.0% for 10 seconds or below 4.5% for 10 seconds, the controller will pause the baseline pump pressure update operation.

5. The concrete pouring method as described in claim 1, characterized in that, After each shutdown of the air-entraining agent metering pump or the defoamer metering pump, the controller initiates a 60-120 second delay protection period. During the delay protection period, the controller suspends the monitoring and comparison functions of gas content data and pump pressure change rate; After the delay protection period ends, the controller resumes its function of monitoring and comparing gas content data and pump pressure change rate.

6. The concrete pouring method as described in claim 1, characterized in that, The controller records the continuous addition time each time the air-inducing agent metering pump or defoamer metering pump is started; When a single continuous addition exceeds 180 seconds, the controller automatically performs a second speed reduction: if defoamer solution is being added, the concrete pump's pumping speed is reduced by 10-15% from 70-80% of the initial pumping speed; if air-entraining agent solution is being added, the concrete pump's pumping speed is reduced by 10-15% from 90-100% of the initial pumping speed. The secondary speed reduction operation continues until 30 seconds after the priming agent metering pump or defoamer metering pump is shut down. After 30 seconds, the concrete pump's pumping speed returned to the speed before this second speed reduction operation.

7. The concrete pouring method as described in claim 1, characterized in that, After the air-entraining agent metering pump or the defoamer metering pump is started, the controller calculates the real-time rate of change of gas content. If the rate of increase in real-time gas content is less than 0.1% / min in volume for 60 seconds when the entraining agent solution is added, the controller will increase the flow rate of the entraining agent solution by 0.5 mL / min. If the rate of decrease in real-time gas content is less than 0.1% / min in volume for 60 seconds after adding defoamer solution, the controller will increase the defoamer solution addition flow rate by 0.5 mL / min. If the rate of increase in real-time gas content is greater than 1.0% / min in volume for 30 seconds when the air-entraining agent solution is added, the controller will reduce the flow rate of the air-entraining agent solution by 0.5 mL / min. If the rate of decrease in real-time gas content is greater than 1.0% / min in volume for 30 seconds when defoamer solution is added, the controller will reduce the defoamer solution addition flow rate by 0.5 mL / min. After the flow rate is adjusted, the controller continues to monitor the real-time rate of change of gas content until it is maintained within the range of 0.2-0.5% / min.

8. The concrete pouring method as described in claim 5, characterized in that, After the air-entraining agent metering pump or defoamer metering pump is shut down and the pumping speed is restored to the initial pumping speed, the controller starts a 60-120s stable monitoring period after a 60s delay protection period. During the stable monitoring period, the controller collects gas content data at a frequency of 0.2 times / s and calculates its range; When the range of air content data during the stable monitoring period exceeds 1.5% by volume, the controller determines that the concrete mixture is in a generally unstable state. The controller sets a continuous pumping speed based on the type of solution previously added: 75-80% of the initial pumping speed if the previously added solution was an antifoaming agent; and 90-95% of the initial pumping speed if the previously added solution was an air-entraining agent. The controller maintains this pumping speed for subsequent operations. In continuous pumping speed operation mode, if the real-time gas content is below 4.5% for 10 seconds and the pump pressure change rate exceeds 0.5 MPa / min, or the real-time gas content is above 6.0% for 10 seconds, the controller will immediately exit the continuous pumping speed operation mode and execute a control process that includes starting the priming agent metering pump or the defoamer metering pump and adjusting the corresponding pumping speed.

9. The concrete pouring method as described in claim 1, characterized in that, The controller records and counts the total number of times the air-inducing agent metering pump and the defoamer metering pump are started per unit time. When the total number of adjustments exceeds 6 within 5 consecutive minutes, the controller determines that the automatic control system is in a state of frequent operation. The controller automatically and temporarily increases the upper limit of the gas content range of 4.5-6.0% by 0.5-0.8% and temporarily decreases the lower limit by 0.5-0.8%. The controller continuously monitors the adjustment frequency. When the total number of adjustments drops below 3 within 5 consecutive minutes, it automatically restores the gas content range to 4.5-6.0% by volume. During the temporary adjustment of the gas content range, the pumping speed is maintained at 85-90% of the initial pumping speed.

Images