Concrete pumping quantity determination method, accelerator control method, system and device

Abstract

The application discloses a concrete pumping volume determination method, a quick-setting agent control method, a system and a device, and the method comprises the following steps: step one, determining a single pumping volume at the time of pumping, wherein the single pumping volume is obtained by averaging the volume of each pumping in a period of time detected by a flowmeter in real time; step two, determining a pumping efficiency according to the ratio of the single pumping volume to the volume of a concrete cylinder; and step three, correcting the theoretical pumping volume in real time according to the pumping efficiency to determine an actual pumping volume. Since the theoretical pumping volume is corrected in real time by the pumping efficiency, the data after the correction is used for subsequent calculation, the accuracy of the concrete volume calculation is improved, the cement content of the concrete and the optimal quick-setting agent mixing rate are combined to control the output of the quick-setting agent, so that the wet spraying construction is rapid, stable and efficient, the wet spraying construction quality is ensured, and the construction cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wet shotcrete construction, and specifically relates to a method for determining the pumping volume of concrete, a method for linkage control of accelerator, a system, a device and a medium. Background Art

[0002] A wet shotcreting machine is a support device required at the initial stage of a tunnel or other projects, which is widely used. During operation, the concrete in the wet shotcreting machine is transported to the spraying device through a pumping pipeline, and then the accelerator is transported to the spraying device by high-pressure air and fully mixed with the concrete, and then sprayed at a high speed onto the construction surface. The concrete containing the accelerator quickly coagulates, thereby forming a support layer.

[0003] If the output control of the accelerator during spraying is not good, it will directly affect the setting time, curing strength and construction cost of the shotcrete. When the accelerator is too little, it will increase the setting time of the concrete, resulting in abnormal flow of the concrete during construction and failing to achieve the final construction effect. Even the concrete will fall off and cause waste, which will directly increase the construction cost and construction duration. When the accelerator is too much, depending on the quality of the accelerator, it will lead to an increase in the setting time of the concrete and a decrease in the final setting strength of the concrete. Therefore, an optimal ratio between the accelerator and the concrete is required during spraying.

[0004] In the existing concrete wet shotcreting construction plan, one is that the operator adjusts the dosage of the accelerator according to his experience and observes the effect of the shotcrete. It depends greatly on the experience and proficiency of the operator, and the effect is not ideal. The other is to simply calculate the required amount of the accelerator according to the theoretical pumping volume to achieve linkage control. However, during the pumping process, it is impossible for the concrete cylinder to suck in full each time, and the pushing cylinder does not push out the full stroke. Therefore, there is a large deviation between the theoretical pumping volume and the actual pumping volume, resulting in a deviation between the accelerator delivery volume and the actual demand, so the control effect of the accelerator dosage is not ideal either. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for determining the pumping volume of concrete, a method for linkage control of accelerator, a system, a device and a medium, aiming at the problem of poor control effect of the accelerator dosage in concrete wet shotcreting construction. This method can control the output of the accelerator according to the optimal ratio of the accelerator and the concrete, so as to achieve fast, stable and efficient wet shotcreting construction.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A method for determining the pumping volume of concrete includes the following steps:

[0008] Step 1: Determine the single pumping volume during pumping. The single pumping volume is obtained by taking the average value of the volume pumped each time over a period of time by real-time detection of the flow meter.

[0009] Step 2: Determine the pumping efficiency based on the ratio of the volume of a single pump to the volume of the concrete cylinder;

[0010] Step 3: Correct the theoretical pumping volume in real time based on the pumping efficiency to determine the actual pumping volume.

[0011] Furthermore, the theoretical pumping volume mentioned in step three is determined by the number of pumping operations obtained from the reversing switch in the pumping mechanism, and then by the number of pumping operations and the volume of the concrete cylinder.

[0012] This invention also provides a method for controlling the dosage of accelerator in a wet spraying machine, which utilizes the concrete pumping volume determination method described above to control the dosage of accelerator, including the following steps:

[0013] Step 1: Estimate the volume of concrete pumped during shotcreting based on the method described above, and calculate the actual cement consumption per unit time during shotcreting based on the estimated volume of concrete pumped.

[0014] Step 2: Determine the optimal amount of accelerator consumed per unit time based on the amount of cement consumed;

[0015] Step 3: Control the speed of the accelerator pump according to the amount of accelerator consumed.

[0016] Furthermore, the cement consumption mentioned in step one is determined based on the concrete pumping volume and the cement content of the concrete.

[0017] Furthermore, the accelerator consumption in step two is the product of the cement consumption in step one and the optimal accelerator dosage rate, wherein the accelerator dosage rate is the ratio of the accelerator to the mass of cement in the concrete.

[0018] Furthermore, the optimal dosage of the accelerator is determined by the operator based on the optimal dosage ratio obtained from the experiment, and by making minor adjustments according to the actual construction conditions on site.

[0019] This invention also provides a wet spraying machine accelerator linkage control system for implementing the above-described wet spraying machine accelerator linkage control method. The system includes a parameter input module, a concrete detection module, a control module, and a signal output module. The parameter input module inputs spraying process-related parameters to the control module. The concrete detection module detects the volume of concrete pumped in a single operation in real time. The control module determines the pumping efficiency based on the acquired volume of concrete pumped in a single operation, and after processing the data, outputs a accelerator pump speed requirement control parameter signal to the signal output module. The signal output module adjusts the accelerator pump speed according to the received accelerator pump speed requirement control parameter signal.

[0020] The present invention also provides a concrete wet spraying device, which uses the above-described wet spraying machine accelerator linkage control method to control the amount of accelerator.

[0021] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the above-described wet spraying machine accelerator linkage control method.

[0022] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0023] This invention determines the actual pumping volume by introducing pumping efficiency, then calculates the cement mass in the concrete actually sprayed per unit time, and combines this with the optimal dosage ratio of the accelerator to obtain the optimal accelerator consumption mass per unit time. This mass is then converted into the accelerator consumption volume per unit time. The actual required rotational speed of the accelerator pump is controlled based on the accelerator consumption volume, thereby achieving linkage control of the accelerator. Because the theoretical pumping volume is corrected in real time by pumping efficiency, the corrected data can be used for subsequent calculations, improving the accuracy of concrete volume calculation. At the same time, by combining the concrete cement content and the optimal accelerator dosage rate to control the accelerator output, a fast, stable, and efficient wet spraying construction is achieved, thereby ensuring the quality of wet spraying construction and reducing construction costs. Attached Figure Description

[0024] Figure 1 This is a flowchart of the method for determining the pumping volume in this invention.

[0025] Figure 2 This is a flowchart of the wet spraying machine accelerator linkage control method in this invention.

[0026] Figure 3 This is a schematic diagram of the computational model of the present invention.

[0027] Figure 4 This is a schematic diagram of the wet spraying machine accelerator linkage control system of the present invention. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings.

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0030] Example 1

[0031] like Figure 1As shown in the figure, this embodiment provides a method for determining the volume of concrete to be pumped, including the following steps:

[0032] Step 1: Determine the single pumping volume during pumping. The single pumping volume is obtained by taking the average value of the volume pumped each time over a period of time by real-time detection of the flow meter.

[0033] Step 2: Determine the pumping efficiency based on the ratio of the volume of a single pump to the volume of the concrete cylinder;

[0034] Step 3: Correct the theoretical pumping volume in real time based on the pumping efficiency to determine the actual pumping volume.

[0035] In this embodiment, to determine the volume of concrete pumped in a single pumping operation (M_single, m³), ​​a flow meter is installed inside the concrete delivery pipe to detect the volume of concrete pumped in real time for each operation (here, volume refers to the actual volume of concrete pushed out by the piston each time it draws material from the hopper). Since the amount of air drawn in with each pumping operation is irregular, the measured value will fluctuate. Therefore, it is necessary to take the average value of multiple sampling data: M_single = (M_1 + M_2… M_x) / X.

[0036] Since it's impossible for the concrete cylinder to be completely filled every time during shotcrete pumping, and the cylinder isn't pushed out for its entire stroke, the theoretical pumping volume obtained through calculation needs to be corrected using a pumping efficiency parameter. Only the corrected data can be used for subsequent calculations to improve accuracy. In this embodiment, the pumping efficiency (n, %) is the ratio of the single pumping volume M_single to the concrete cylinder volume V_concrete_cylinder, specifically calculated as n = (M_single / V_concrete_cylinder) * 100%.

[0037] In this embodiment, the theoretical pumping volume (Mtheoretical, m³ / H) mentioned in step three is determined by the pumping number C obtained from the reversing switch in the pumping mechanism, and then by the pumping number C and the concrete cylinder volume Vconcrete cylinder. The specific calculation formula is Mtheoretical = Vconcrete cylinder * C.

[0038] In this embodiment, the actual pumping volume mentioned in step three is obtained by multiplying the theoretical pumping volume by the pumping efficiency. Because the theoretical pumping volume is continuously corrected by adjusting the pumping efficiency, the concrete volume calculation becomes more accurate.

[0039] It should be noted that this method calculates pumping efficiency by periodically sampling the volume of each pumping operation over a period of time and then averaging the average volume as the volume of a single pumping operation. Since the volume of a single pumping operation is constantly changing, the pumping efficiency calculated through continuous iteration is also constantly changing. Therefore, the theoretical pumping volume is corrected in real time based on the changing pumping efficiency.

[0040] Example 2

[0041] This embodiment provides a method for linkage control of accelerator in wet spraying machines;

[0042] like Figure 2 and Figure 3 As shown, the wet spraying machine accelerator linkage control method in this embodiment controls the accelerator dosage according to the concrete pumping volume determination method described in Example 1, including the following steps:

[0043] Step 1: Obtain the actual mass of cement consumed per unit time during the spraying process;

[0044] Step 2: Determine the optimal accelerator consumption per unit time based on the cement consumption mass;

[0045] Step 3: Control the speed of the accelerator pump according to the amount of accelerator consumed.

[0046] In this embodiment, step one specifically involves estimating the concrete pumping volume during shotcreting operations according to the method described in Embodiment 1, and calculating the actual cement consumption per unit time during the shotcreting process based on the estimated concrete pumping volume. That is, the cement consumption is determined by multiplying the corrected actual pumping volume by the concrete cement content, which is also determined by multiplying the theoretical pumping volume, pumping efficiency, and concrete cement content.

[0047] It's important to note that pumping efficiency is introduced for correction because, according to the flowmeter's measurement principle, a signal is only generated after fluid has passed through. Therefore, there's a delay in the flowmeter's signal acquisition, making it impossible to directly control the accelerator pump's speed using the flowmeter data at the current time t (because in actual construction, both the concrete pump and the accelerator pump operate continuously; the accelerator pump is still running at the moment the flowmeter acquires the signal). Directly using flowmeter data to control the accelerator pump is equivalent to using the flowmeter data at time t to control the accelerator pump speed at time t+1. There's always a time difference between the two. If the concrete pumping volume at time t+1 differs significantly from that at time t, this will cause a larger error, resulting in a complete mismatch between the accelerator and concrete mix proportions.

[0048] In this embodiment, the concrete cement content (α, kg / m³) refers to the weight of cement contained in each cubic meter of commercial concrete purchased by the construction party.

[0049] In this embodiment, the mass of accelerator consumed in step two is determined by multiplying the mass of cement consumed in step one by the optimal accelerator dosage.

[0050] In this embodiment, the accelerator dosage rate (K, ranging from 0.5% to 10%) is a recommended range for the ratio of accelerator to cement mass in concrete. Since the accelerator reacts with cement, it is the ratio of accelerator to cement mass in concrete.

[0051] In this embodiment, the optimal dosage of the quick-setting agent is determined by the operator based on the optimal dosage ratio obtained from the experiment and by making minor adjustments according to the actual construction conditions on site.

[0052] In this embodiment, step three specifically involves first calculating the volume of accelerator consumed per unit time based on the mass of accelerator consumed, and then controlling the actual required speed of the accelerator pump based on the volume of accelerator consumed.

[0053] In this embodiment, the volume of accelerator consumed is the ratio of the mass of accelerator consumed to the density of the accelerator. The density of the accelerator (ρ, kg / L) is a parameter explicitly defined in the accelerator purchased by the construction party.

[0054] In this embodiment, the actual required rotational speed (R, r / min) of the accelerator pump is the ratio of the volume of accelerator consumed to the pump's displacement. That is, the required pump speed is calculated based on the real-time calculated demand for accelerator. The pump displacement (β, cc / rpm) is the flow rate pumped per revolution, a fixed parameter value for the pump.

[0055] The specific calculation process of this invention is as follows:

[0056] 1. Calculate the cement consumption per hour (KG) = Theoretical pumping volume * Pumping efficiency * Concrete cement content; that is: Mtheoretical * n * α;

[0057] 2. Calculate the cement consumption per minute (kg) = cement consumption per hour (kg) / 60; that is: Mtheoretical * n * α / 60;

[0058] 3. Calculate the mass of accelerator consumed per minute (KG) = mass of cement consumed per minute (KG) * accelerator dosage rate; that is: Mtheoretical * n * α / 60 * K;

[0059] 4. Calculate the volume of accelerator consumed per minute (L) = mass of accelerator consumed per minute (KG) / density of accelerator; that is: Mtheoretical * n * α / 60 * K / ρ;

[0060] 5. Calculate the actual required speed (R) of the accelerator pump = Volume of accelerator consumed per minute (L) / accelerator pump displacement; that is: M theoretical * n * α / 60 * K / ρ / (β / 1000).

[0061] In this embodiment, the accelerator pump can be driven by a proportional valve and a hydraulic motor, or by a frequency converter and a motor, or other driving modes. Based on the calculated actual required speed of the accelerator pump, the linkage control of the accelerator can be achieved simply by accurately controlling the pump speed during construction.

[0062] Through actual construction comparison, this control method reduces the overall material loss rate from 20% to 5% compared to the original method; especially in the tunnel arch shotcrete construction process, the material loss rate is significantly reduced from 30% to 8%; the amount of quick-setting agent used is also much less than before, saving an average of 100L of quick-setting agent per construction shift.

[0063] Example 3

[0064] like Figure 4 As shown, this embodiment provides a wet spraying machine accelerator linkage control system for implementing the wet spraying machine accelerator linkage control method described in Embodiment 2. The system includes a parameter input module, a concrete detection module, a control module, and a signal output module. The parameter input module inputs spraying process-related parameters to the control module. The concrete detection module detects the volume of concrete pumped in a single operation in real time. The control module determines the pumping efficiency based on the acquired volume of concrete pumped in a single operation, and after processing the data, outputs a accelerator pump speed demand control parameter signal to the signal output module. The signal output module adjusts the accelerator pump speed according to the received accelerator pump speed demand control parameter signal.

[0065] In this embodiment, the parameters related to the spraying process include, but are not limited to, inputting values ​​such as concrete cement content, accelerator density, accelerator pump discharge rate, theoretical pumping volume, and accelerator dosage rate to the control module. It is understood that the theoretical pumping volume can also be calculated by the control module by inputting the number of pumping operations per unit time and the volume of the concrete cylinder.

[0066] In this embodiment, the control module iteratively calculates the pumping efficiency based on the constantly changing single pumping volume, and then corrects the theoretical pumping volume in real time based on the iterative pumping efficiency to determine the actual pumping volume. Then, it calculates the actual required speed of the accelerator pump R=Mtheoretical*n*α / 60*K / ρ / (β / 1000) according to the calculation method described in Embodiment 2, thereby outputting the actual required speed control parameter signal of the accelerator pump to the signal output module.

[0067] In this embodiment, the concrete detection module includes a flow meter built into the concrete delivery pipe. The flow meter detects the volume of each pump in real time and feeds the detection data back to the control module.

[0068] This embodiment also includes a accelerator pump drive module, used to adjust the speed of the accelerator pump according to the accelerator pump speed control parameter signal output by the signal output module. In this embodiment, the accelerator pump drive module may include an electro-proportional valve and a hydraulic motor, or it may include a frequency converter and a motor, or other drive modes.

[0069] Example 4

[0070] This embodiment provides a concrete wet spraying device, which uses the wet spraying machine accelerator linkage control method described in Embodiment 2 to control the amount of accelerator.

[0071] Example 5

[0072] This embodiment provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the wet spraying machine accelerator linkage control method described in Embodiment 2.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for linkage control of accelerator in a wet spraying machine, characterized in that, Includes the following steps: Step 1: Install a flow meter in the concrete delivery pipe. The flow meter detects the volume of each pumping operation over a period of time in real time and takes the average value to obtain the single pumping volume. The pumping efficiency is determined based on the ratio of the single pumping volume to the volume of the concrete cylinder. The theoretical pumping volume is corrected in real time based on the pumping efficiency to estimate the actual pumping volume. The actual cement consumption per unit time during the shotcreting process is calculated based on the estimated concrete pumping volume. Step 2: Determine the optimal amount of accelerator consumed per unit time based on the amount of cement consumed; Step 3: Control the speed of the accelerator pump according to the amount of accelerator consumed.

2. The wet spraying machine accelerator linkage control method according to claim 1, characterized in that, The amount of cement consumed in step one is determined based on the volume of concrete pumped and the cement content of the concrete.

3. The wet spraying machine accelerator linkage control method according to claim 1, characterized in that, The accelerator consumption mentioned in step two is the product of the cement consumption mentioned in step one and the optimal accelerator dosage rate, wherein the accelerator dosage rate is the ratio of the accelerator to the cement mass in the concrete.

4. The wet spraying machine accelerator linkage control method according to claim 3, characterized in that, The optimal dosage of the quick-setting agent is determined by the operator based on the optimal dosage ratio obtained from the experiment and by making minor adjustments according to the actual construction conditions on site.

5. The wet spraying machine accelerator linkage control method according to claim 1, characterized in that, The theoretical pumping volume mentioned in step one is determined by the number of pumping operations obtained from the reversing switch in the pumping mechanism, and then by the number of pumping operations and the volume of the concrete cylinder.

6. A wet spraying machine accelerator linkage control system, used to implement the wet spraying machine accelerator linkage control method according to any one of claims 1-5, characterized in that, The system includes a parameter input module, a concrete detection module, a control module, and a signal output module. The parameter input module is used to input spraying process-related parameters to the control module. The concrete detection module is used to detect the volume of concrete pumped in a single operation in real time. The control module determines the pumping efficiency based on the acquired volume of concrete pumped in a single operation, and after processing the data, outputs a speed control parameter signal for the accelerator pump to the signal output module. The signal output module adjusts the speed of the accelerator pump based on the received speed control parameter signal.

7. A concrete wet spraying device, characterized in that, The dosage of the accelerator is controlled by the wet spraying machine accelerator linkage control method described in any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the wet spraying machine accelerator linkage control method according to any one of claims 1-5.

Images