Automatic detection system and detection method for roller compacted concrete Vickers consistency

Abstract

The invention discloses an automatic roller compacted concrete Vitro consistency detection system, which comprises a mechanical execution module, an intelligent control and data acquisition module and an error compensation module, and is characterized in that the mechanical execution module and the intelligent control and data acquisition module are connected through mechanical coupling, and the intelligent control and data acquisition module and the error compensation module are connected through mechanical coupling. The automatic detection method comprises the following steps: S1, initializing equipment and setting parameters; s2, automatic loading and pre-compaction; s3, synchronous linkage detection and data acquisition; s4, intelligent terminal point identification and timing stop; and S5, performing error compensation and data output. Through automatic design of the mechanical execution module, manual operation is not needed, introduction of personal errors is effectively avoided, and the accuracy of a detection result is improved. And the intelligent control and data acquisition module is adopted, so that automatic completion, monitoring and real-time data acquisition of the detection process are realized, errors caused by manual recording in a traditional method are overcome, and the efficiency of detection work and the accuracy of data are improved.

Description

Technical Field

[0001] This invention relates to the field of concrete performance testing technology, specifically to an automatic testing system and method for Vebe consistency of roller-compacted concrete. Background Technology

[0002] Roller-compacted concrete (RCC) is widely used in water conservancy, transportation, and construction projects due to its advantages such as high strength, good compaction, and high construction efficiency. As a core indicator for evaluating the workability of RCC mixes, Vebe consistency directly determines the compaction effect, homogeneity, and subsequent mechanical properties of the concrete. However, traditional methods for testing the Vebe consistency of RCC have many problems, affecting the accuracy and efficiency of the test results.

[0003] Currently, the industry commonly uses the Vebe instrument method for testing. This method requires manual completion of the entire process: "loading material – layered compaction – removing the loading cylinder – lowering the transparent disc – starting vibration – visually judging the endpoint – manually stopping the instrument." This method suffers from problems such as operational delays, large endpoint judgment errors, and sensitivity to environmental interference. As a result, the test results are affected by human error and external environmental factors, making it difficult to meet the requirements for precise quality control in roller-compacted concrete construction.

[0004] Specifically, traditional testing methods have the following drawbacks: ① There are many manual operation steps, which can easily introduce errors, and the judgment time difference between different people can reach 0.5s to 2s, which has a significant impact on low-consistency (Vebe time <10s) roller-compacted concrete; ② Changes in temperature, humidity and wind speed at the construction site will accelerate the evaporation of moisture on the concrete surface, resulting in a longer Vebe time. In high temperature or windy weather, the error can be expanded to more than 20%.

[0005] To address the aforementioned issues, Chinese Patent Publication No. CN212410366U discloses a Vebe consistency tester for concrete. This tester uses a light sensor to detect the concrete as the endpoint condition for the vibration to stop. However, this method is easily affected by the surface condition of the concrete, such as air bubbles or aggregate segregation. The detection accuracy of the light sensor is also easily affected by the external environment and equipment installation. Furthermore, the light sensor can only detect whether the surface is covered and cannot correlate with the density.

[0006] These problems severely restrict the accuracy and efficiency of Vebe consistency testing for roller-compacted concrete, and there is an urgent need for a fully automated, high-precision testing method and device to overcome these shortcomings. Summary of the Invention

[0007] To address the aforementioned technical problems, an automatic detection system and method for Vebe consistency of roller-compacted concrete are provided. This system aims to overcome the shortcomings of traditional Vebe consistency detection methods, such as large human error, low detection efficiency, and weak resistance to environmental interference, thereby achieving accurate and efficient detection of Vebe consistency of roller-compacted concrete and improving the intelligence level of the instruments and equipment.

[0008] The technical solution of the present invention: An automatic Vebe consistency detection system for roller-compacted concrete includes a mechanical execution module, an intelligent control and data acquisition module, and an error compensation module. The mechanical execution module and the intelligent control and data acquisition module are mechanically coupled together, and the intelligent control and data acquisition module and the error compensation module are also mechanically coupled together.

[0009] The mechanical execution module includes a quantitative feeding unit, a synchronous linkage execution unit, and a vibration control unit; The quantitative feeding unit includes a feeding hopper with adjustable volume; The synchronous linkage execution unit includes an automatic lifting loading cylinder, a pressure sensing transparent disc, and a constant temperature and humidity detection chamber. The automatic lifting loading cylinder is installed inside the constant temperature and humidity detection chamber. Each side of the automatic lifting loading cylinder is provided with a vertical slide rail, and a slider is configured on the slide rail. A displacement sensor is configured on the slider. The automatic lifting loading cylinder is mounted on the slide rail via the slider. The slider is connected to a lead screw drive device, which is connected to a servo motor. The automatic lifting loading cylinder is matched and installed with the loading hopper. The pressure sensing transparent disc includes a transparent disc body and pressure sensors evenly distributed at the bottom of the disc body. The disc body has a sealed groove for cable routing inside. The edge of the disc body has a junction box for connecting the cable. The pressure sensor uses a shielded cable to connect to the intelligent control and data acquisition module through the junction box. The constant temperature and humidity testing chamber is equipped with a constant temperature heating film, a humidity sensor, a temperature sensor, and a light sensor. The constant temperature heating film is composed of a high-temperature resistant polyester film and a resistance wire inside the polyester film. The resistance wire is connected to a temperature and humidity controller via wires. The temperature sensor is connected to the temperature and humidity controller. An atomizing and humidifying device is installed on the top of the constant temperature and humidity testing chamber. The atomizing and humidifying device includes an ultrasonic atomizer, a nozzle, and a water tank. The nozzle is installed around the top of the constant temperature and humidity testing chamber. The humidity sensor is connected to the temperature and humidity controller. The vibration control unit includes a vibrator and a motor controller. The vibrator is fixedly connected to the bottom of the constant temperature and humidity testing chamber via a shock-absorbing rubber pad. The vibrator is a vibration motor, which is connected to the motor controller via a power cord.

[0010] The intelligent control and data acquisition module includes a processor, a timer, a humidity sensor, a temperature sensor, and a wireless transmission unit; The processor is located in the control box on the side of the constant temperature and humidity testing chamber. It is responsible for receiving data from each sensor, controlling the actions of each actuator, and coordinating the timing of the entire testing process. The processor communicates with the timer, pressure sensor, humidity sensor, temperature sensor, and wireless transmission unit via a data bus to achieve rapid data transmission and processing. The timer is integrated on the processor's circuit board; The temperature sensor and humidity sensor are synchronously arranged at the top and middle of the constant temperature and humidity testing chamber to collect the temperature and humidity environmental parameters inside the constant temperature and humidity testing chamber. The wireless transmission unit interacts with the processor via serial communication, and the wireless transmission unit connects to the terminal device using a Bluetooth or 4G module.

[0011] The error compensation module incorporates temperature and humidity compensation algorithms, aggregate gradation compensation algorithms, and data anomaly removal algorithms to dynamically correct detection errors.

[0012] An automatic method for detecting the Vebe consistency of roller-compacted concrete includes the following steps: S1: Device initialization and parameter settings; S2: Automatic loading and pre-compaction; S3: Synchronous linkage detection and data acquisition; S4: Intelligent endpoint recognition and timer stop; S5: Error compensation and data output.

[0013] In step S1, the device initialization and parameter setting include the following steps: a1. Start the automatic detection system and set the detection parameters through the intelligent control and data acquisition module. The detection parameters include the maximum particle size of concrete aggregate, target temperature, target humidity, loading amount, pre-compaction time, vibration frequency and vibration amplitude information. a2. Calibrate the automatic detection system using standard sand with known Vebe time.

[0014] In step S2, the automatic loading and pre-compaction includes the following steps: b1. Pour the roller-compacted concrete mix to be tested into the hopper, and the hopper will inject the concrete into the testing area of ​​the constant temperature and humidity testing chamber in one go; b2. Start the vibration control unit to pre-compact the concrete using the vibrator; b3. Detect whether the concrete surface is completely covered by the light sensor. If it is not completely covered, return to step b2 to continue oscillation pre-compaction. If it is completely covered, proceed to step S3.

[0015] In step S3, the synchronous linkage detection and data acquisition includes the following steps: c1. The servo motor drives the automatic lifting loading cylinder to rise, and the pressure sensing transparent disc automatically descends to fit the concrete surface. The center of the automatic lifting loading cylinder, the pressure sensing transparent disc and the detection area coincide. c2. Start the vibrator; the vibrator will begin to vibrate according to the set parameters. c3. The pressure sensor and timer of the transparent pressure sensing disc work synchronously to collect pressure data and time data and transmit them to the processor in real time; c4. Monitor changes on the concrete surface in real time using a light sensor. If a significant change is detected on the concrete surface, return to step c1 and repeat the detection.

[0016] In step S4, the intelligent endpoint recognition and timing stop includes the following steps: d1. The processor analyzes the data collected by the pressure sensor in real time. When the pressure value of all pressure sensors is ≤0.5N, it is determined that the transparent disc of the pressure sensor is completely supported by the concrete without any obvious gaps. The processor immediately controls the vibrator to stop vibrating and stops the timer. At this time, the time displayed by the timer is the initial time of the initial Vebe consistency VC value, which is t0. d2. Confirm whether the ambient light intensity around the detection area is within the preset range using a light sensor. If it is not within the preset range, return to step c1 and perform the detection again.

[0017] In step S5, the error compensation and data output include the following steps: e1. The error compensation module calls the temperature and humidity compensation algorithm, aggregate gradation compensation algorithm, and data anomaly removal algorithm to dynamically correct the detection error and correct the initial Vebe consistency (VC) value; e2. Temperature and humidity compensation: Based on the data from the humidity sensor and temperature sensor inside the constant temperature and humidity testing chamber, a temperature and humidity correction formula is used for correction. e3. Aggregate gradation compensation: Based on the maximum aggregate size set in step a1, the aggregate gradation database is called to correct the difference in vibration resistance caused by coarse aggregate; e4. Data anomaly removal: Through pressure change curve smoothness analysis, outlier data with single pressure fluctuations >5N are removed, and the result is optimized by using the average of 5 adjacent valid data sets; e5. The final Vebe consistency value, pressure change curve, environmental parameters, and detection time data are transmitted to the terminal via the wireless transmission unit, and the terminal device automatically generates detection records and reports.

[0018] The beneficial effects of this invention are: This invention, through the automated design of the mechanical execution module, eliminates the need for manual operation, effectively avoiding the introduction of human error and significantly improving the accuracy of test results. Simultaneously, the use of intelligent control and data acquisition modules enables automatic completion, monitoring, and real-time data acquisition of the testing process, overcoming errors from manual recording in traditional methods and improving the efficiency and accuracy of the testing work. The use of a constant temperature and humidity testing chamber, along with humidity and temperature sensors, effectively isolates the test from temperature and humidity interference in the construction environment. Combined with an error compensation algorithm, it can maintain a testing error within ±0.5 seconds in complex environments ranging from -5℃ to 40℃ and humidity from 30% to 90%, significantly improving the test's resistance to environmental interference and its strong adaptability. Furthermore, through a quantitative loading unit and pre-compaction control, the uniformity and density of the concrete are ensured, reducing inconsistencies and uneven areas caused by manual operation, thereby improving the authenticity and reliability of the test results. Attached Figure Description

[0019] Figure 1 This is a front view schematic diagram of the automatic detection system of the present invention; Figure 2 This is a rear view schematic diagram of the automatic detection system of the present invention; Figure 3 This is a schematic diagram of the synchronous linkage execution unit of the present invention; Figure 4 This is a schematic diagram of the arrangement of the pressure sensing transparent disc of the present invention; Figure 5 This is a schematic diagram of the interior of the constant temperature and humidity testing chamber of the present invention; Figure 6 This is a schematic diagram of the interior of the constant temperature heating film of the present invention; Figure 7 This is a schematic diagram of the vibration control unit of the present invention; Figure 8 This is a schematic diagram of the indoor test pressure change curve and the Vebe time determination of the present invention; Figure 9 This is a schematic diagram of the pressure change curve and Vebe time determination in the field test of this invention.

[0020] Reference numerals: 1-Filling hopper, 2-Automatic lifting filling cylinder, 3-Pressure sensing transparent disc, 4-Constant temperature and humidity detection chamber, 5-Slide rail, 6-Slider, 7-Screw drive device, 8-Servo motor, 9-Disc body, 10-Pressure sensor, 11-Wire trough, 12-Gathering box, 13-Constant temperature heating film, 14-Humidity sensor, 15-Light sensor, 16-Polyester film, 17-Resistance wire, 18-Temperature and humidity controller, 19-Power switch, 20-Sonic atomizer, 21-Nozzle, 22-Temperature sensor, 23-Vibrator, 24-Motor controller, 25-Shock-absorbing rubber pad, 26-Processor, 27-Timer, 28-Water tank, 29-Mold, 30-Display screen, 31-USB interface. Detailed Implementation

[0021] refer to Figures 1-9 An automatic Vebe consistency detection system for roller-compacted concrete includes a mechanical execution module, an intelligent control and data acquisition module, and an error compensation module. The mechanical execution module and the intelligent control and data acquisition module are mechanically coupled together, and the intelligent control and data acquisition module and the error compensation module are also mechanically coupled together.

[0022] In this application, the overall system dimensions are 1200mm in length, 800mm in width, and 1500mm in height, and it can perform two sets of tests simultaneously; The mechanical execution module includes a quantitative feeding unit, a synchronous linkage execution unit, and a vibration control unit; The quantitative feeding unit includes a feeding hopper 1 with adjustable volume, used to inject the roller-compacted concrete mixture into the testing area in one go, avoiding the unevenness of manual feeding.

[0023] The synchronous linkage execution unit includes an automatic lifting loading cylinder 2, a pressure sensing transparent disc, and a constant temperature and humidity detection chamber 4. The automatic lifting loading cylinder 2 is installed inside the constant temperature and humidity testing chamber 4.

[0024] In this application, the automatic lifting loading cylinder 2 is located below the mold 29. The automatic lifting loading cylinder 2 is made of high-strength aluminum alloy with a wall thickness of approximately 3mm, ensuring structural stability and lightweight. The internal dimensions of the automatic lifting loading cylinder 2 strictly conform to standards: a bottom diameter of 200mm, a top diameter of 100mm, and a height of 300mm. Concrete is injected into the automatic lifting loading cylinder 2 through the metered loading hopper 1, which constrains the concrete into a standard frustum-shaped accumulation, avoiding problems such as "uneven accumulation height and loose edges" that occur during manual loading, ensuring that the initial volume and density of the concrete are consistent in each test.

[0025] The automatic lifting loading cylinder 2 has a vertical slide rail 5 on each side. A slider 6 is mounted on each slide rail 5, and a displacement sensor is mounted on each slider 6. The automatic lifting loading cylinder 2 is mounted on the slide rail 5 via the slider 6. A lead screw drive device 7 is connected to the slider 6, and a servo motor 8 is connected to the lead screw drive device 7. The automatic lifting loading cylinder 2 is matched and installed with the loading hopper 1. Because the slider 6 is connected to the lead screw drive device 7, and the lead screw drive device 7 is connected to the servo motor 8, after the servo motor 8 is started, the lead screw rotates, driving the slider 6 to move up and down along the slide rail, realizing the rapid lifting and lowering of the automatic lifting loading cylinder 2. This ensures that the lifting speed of the automatic lifting loading cylinder 2 is precisely controlled at 50mm / s, and the positioning accuracy can reach ±0.5mm. In this application, the displacement sensor uses a mature product from the prior art, model Omron / E6B2-CWZ6C.

[0026] The pressure sensing transparent disc includes a transparent disc body 9 and pressure sensors 10 evenly distributed at the bottom of the disc body 9. The disc body 9 has a sealed groove 11 for cable lead-out. The edge of the disc body 9 has a junction box 12 for connecting the cable. The pressure sensor 10 uses a shielded cable to connect to the intelligent control and data acquisition module through the junction box 12. In this application, the main body 9 of the disc is made of high-strength transparent acrylic material, with a diameter of 230mm and a thickness of 10mm. The surface is flat and smooth, making it easy to observe the state of the concrete surface. Eight pressure sensors 10, model Honeywell / FSG15N1A, are evenly distributed at the bottom of the main disc 9, arranged in a circular array with an interval of approximately 85mm. Each pressure sensor 10 has a range of 0N to 50N and an accuracy of 0.1N. It can detect changes in the supporting force of concrete on the main disc 9 in real time and convert the pressure signal into an electrical signal, which is then transmitted to the intelligent control and data acquisition module. The wiring of the pressure sensors 10 is led out through a pre-installed wire groove 11 inside the main disc 9. The wire groove 11 is sealed to prevent concrete slurry from entering and affecting the signal transmission. The outgoing cable connects to a junction box 12 on the edge of the main disc 9, and then to the data acquisition port of the intelligent control and data acquisition module via a shielded cable, ensuring the stability and accuracy of signal transmission.

[0027] The constant temperature and humidity detection chamber 4 is equipped with a constant temperature heating film 13, a humidity sensor 14, a temperature sensor 22, and a light sensor 15. The constant temperature heating film 13 is composed of a high-temperature resistant polyester film 16 and a resistance wire 17 inside the polyester film. The resistance wire 17 is connected to a temperature and humidity controller 18 through wires. The temperature sensor 22 is connected to the temperature and humidity controller 18. An atomizing humidity device is installed on the top of the constant temperature and humidity detection chamber 4. The atomizing humidity device includes an ultrasonic atomizer 20, a nozzle 21, and a water tank 28. The nozzle 21 is installed around the top of the constant temperature and humidity detection chamber 4. The humidity sensor 14 is connected to the temperature and humidity controller 18. In this application, the constant temperature and humidity testing chamber 4 has a rectangular structure. The outer shell is made of double-layer stainless steel plates, and the middle is filled with 50mm thick thermal insulation material, such as polyurethane foam, to effectively reduce heat exchange between the inside and outside of the chamber. The internal dimensions of the constant temperature and humidity testing chamber 4 are 1000mm in length, 500mm in width, and 1500mm in height.

[0028] The inner walls of the constant temperature and humidity testing chamber 4 are covered with a constant temperature heating film 13. The constant temperature heating film 13 is composed of a high temperature resistant polyester film 16 and an internal resistance wire 17. The temperature and humidity controller 18 achieves precise temperature control of ±1℃. The resistance wire 17 is connected to the temperature and humidity controller 18 through wires. The temperature and humidity controller 18 collects the temperature data inside the constant temperature and humidity testing chamber 4 in real time through the temperature sensor 14, and automatically adjusts the power of the constant temperature heating film 13 according to the set temperature value to achieve precise temperature control.

[0029] The constant temperature and humidity testing chamber 4 is equipped with an atomizing and humidifying device, which includes an ultrasonic atomizer 20, a nozzle 21, and a water tank 28. The nozzle 21 is distributed around the top of the constant temperature and humidity testing chamber 4 and can convert water into tiny particles and spray them evenly inside the constant temperature and humidity testing chamber 4.

[0030] The atomizing humidification device is regulated by a temperature and humidity controller 18. A humidity sensor 14 monitors the humidity inside the constant temperature and humidity chamber 4 in real time. When the humidity is below a set lower limit, the controller activates the atomizing humidification device to increase the humidity; when the humidity is above an upper limit, the controller stops the atomizing humidification device to maintain the humidity inside the chamber within a stable range. In this application, the atomizing humidification device is an atomizer. The temperature and humidity testing chamber has a double-sealed transparent door, which allows operators to observe the monitoring process without affecting the internal environment.

[0031] The vibration control unit includes a vibrator 24 and a motor controller 25, which can automatically adjust the vibration parameters according to the testing requirements to ensure that the vibration intensity meets the standard requirements. The vibrator 23 is fixedly connected to the bottom of the constant temperature and humidity testing chamber 4 via a shock-absorbing rubber pad 25, which can reduce the impact of vibration on the constant temperature and humidity testing chamber 4 and other components.

[0032] The vibrator 23 is a vibrating motor, which is connected to the motor controller 24 via a power cord, and the vibration intensity and time can be adjusted according to the testing requirements.

[0033] The vibrator 23 is an HZP-5 vibrator produced by Shanghai Construction Road & Bridge Machinery Equipment Co., Ltd., with a working frequency of 50Hz and an amplitude of 0.5mm.

[0034] The intelligent control and data acquisition module includes a processor 26, a timer 27, a humidity sensor 14, a temperature sensor 22, and a wireless transmission unit.

[0035] The processor 26 is located in the control box on the side of the constant temperature and humidity detection chamber 4. It is responsible for receiving data from each sensor, controlling the actions of each actuator, and coordinating the timing of the entire detection process. In this application, the control box is equipped with a display screen 30, a USB interface 31, and a power switch 19.

[0036] The processor 26 communicates with the timer 27, pressure sensor 10, humidity sensor 14, temperature sensor 22, and wireless transmission unit via a data bus to achieve rapid data transmission and processing. In this application, the processor 26 is used to control the timing linkage of each module, and the timer accuracy is ±0.01s; the processor 26 is placed in the control box on the side of the constant temperature and humidity detection chamber 4, and the control box has good electromagnetic shielding performance; the processor 26 model is GigaDevice / GD32F470.

[0037] The timer 27 is integrated on the circuit board of the processor 26. The timer 27 uses a high-precision crystal oscillator as the clock reference, and the timing accuracy can reach ±0.01s. During the detection process, the timer 27 starts timing the instant the vibration begins and stops timing when the endpoint identification condition is met. The recorded time is the initial value of Vebe consistency, and this time data is transmitted to the processor 26 in real time for subsequent processing.

[0038] The temperature sensor 14 and humidity sensor 22 are synchronously arranged at the top and middle positions of the constant temperature and humidity detection chamber 4 to collect temperature and humidity environmental parameters inside the constant temperature and humidity detection chamber 4. In this application, humidity sensor 14 and temperature sensor 22 are used to collect environmental parameters inside the constant temperature and humidity detection chamber 4. They are installed near the center inside the chamber. Humidity sensor 14 is a Honeywell / HIH5030, and temperature sensor 22 is a Maxim Integrated / DS18B20, both cylindrical in shape with a diameter of approximately 20mm and a length of 50mm. Humidity sensor 14 and temperature sensor 22 are connected to processor 26 via an RS485 communication interface, enabling real-time acquisition of temperature and humidity data within the constant temperature and humidity detection chamber 4. The data is transmitted to processor 26 in digital signal form, providing environmental parameter data for the error compensation module. The wireless transmission unit interacts with the processor 26 via serial communication, and the wireless transmission unit connects to the terminal device using a Bluetooth or 4G module.

[0039] In this application, the wireless transmission unit uses a Bluetooth or 4G module to transmit the detection data to the terminal device, which is convenient for selection according to the actual use scenario; the wireless transmission unit and the processor interact with each other through serial communication to ensure the stability and reliability of data transmission.

[0040] The error compensation module incorporates temperature and humidity compensation algorithms, aggregate gradation compensation algorithms, and data anomaly removal algorithms to dynamically correct detection errors. The specific methods are as follows: An automatic method for detecting the Vebe consistency of roller-compacted concrete includes the following steps: S1: Device initialization and parameter settings, including the following steps: a1. Start the automatic detection system and set the detection parameters through the intelligent control and data acquisition module. The detection parameters include the maximum particle size of concrete aggregate, target temperature, target humidity, loading amount, pre-compaction time, vibration frequency and vibration amplitude information. After the detection parameters are entered, the constant temperature and humidity detection chamber 4 automatically adjusts to the target environmental parameters.

[0041] a2. Calibrate the automatic detection system using standard sand with known Vebe time to ensure that the pressure sensor 10 and timer 27 meet the accuracy requirements.

[0042] S2: Automatic loading and pre-compaction: Includes the following steps: b1. Pour the roller-compacted concrete mixture to be tested into the loading hopper 1. The loading hopper 1 injects the concrete into the testing area of ​​the constant temperature and humidity testing chamber 4 in one go. b2. Start the vibration control unit and use the vibrator 23 to pre-compact the concrete with vibration for 3 to 5 seconds. This replaces the traditional manual layered compaction and ensures that the concrete density variation coefficient is <3%. b3. Detect whether the concrete surface is completely covered by the light sensor 15. If it is not completely covered, return to step b2 to continue oscillation pre-compaction. If it is completely covered, proceed to step S3.

[0043] S3: Synchronous linkage detection and data acquisition, including the following steps: c1. Servo motor 8 drives the automatic lifting loading cylinder 2 to rise, and the pressure sensing transparent disc 3 automatically descends to fit the concrete surface. The automatic lifting loading cylinder 2, the pressure sensing transparent disc 3 and the center of the detection area coincide. c2. Start the vibrator 23. The vibrator 23 will start vibrating according to the set parameters. c3. The pressure sensor 10 of the pressure sensing transparent disk 3 works synchronously with the timer 27 to collect pressure data and time data and transmit them to the processor 26 in real time; Specifically, the eight distributed pressure sensors 10 of the pressure sensing transparent disk 3 work synchronously with the timer 27, collecting 100 sets of pressure and time data per second and transmitting them to the processor in real time. c4. Monitor the changes on the concrete surface in real time using the light sensor 15. If a significant change is detected on the concrete surface, return to step c1 and repeat the detection.

[0044] S4: Intelligent endpoint recognition and timing stop, including the following steps: d1. The processor 25 analyzes the data collected by the pressure sensor 10 in real time. When the pressure value of all pressure sensors 10 is ≤0.5N, it is determined that the pressure sensing transparent disc is completely supported by the concrete and there is no obvious gap. The processor 25 immediately controls the vibrator 23 to stop vibrating and stops the timer 27. At this time, the time displayed by the timer 27 is the initial time of the initial Vebe consistency VC value, which is t0. d2. Use light sensor 15 to confirm whether the ambient light intensity around the detection area is within the preset range. If it is not within the preset range, return to step c1 and perform the detection again.

[0045] S5: The error compensation and data output include the following steps: e1. The error compensation module calls the temperature and humidity compensation algorithm, aggregate gradation compensation algorithm, and data anomaly removal algorithm to dynamically correct the detection error and correct the initial Vebe consistency (VC) value; e2. Temperature and humidity compensation: Based on the data from humidity sensor 14 and temperature sensor 22 inside the constant temperature and humidity detection chamber 4, a temperature and humidity correction formula is used for correction; the correction formula is as follows: (Equation 1) Where T -- measured temperature; ω -- measured humidity; t0 is the initial time of the initial Vebe consistency VC value; e3. Aggregate gradation compensation: Based on the maximum aggregate size set in step a1, the aggregate gradation database is called to correct the difference in vibration resistance caused by coarse aggregate; e4. Data anomaly removal: Through pressure change curve smoothness analysis, abnormal data with single pressure fluctuations >5N are removed, and the result is optimized by using the average value of 5 adjacent valid data sets. e5. The final Vebe consistency value, pressure change curve, environmental parameters, and detection time data are transmitted to the terminal via the wireless transmission unit, and the terminal device automatically generates detection records and reports.

[0046] The following provides an example to illustrate this application: Taking C as an example... 90 Taking the indoor test of 20-grade roller-compacted concrete as an example, the designed VC value is 3.0s, and the specific implementation steps are as follows: Device initialization and parameter settings Start the system and set the detection parameters through the intelligent control module. Enter the following parameters in sequence: maximum aggregate size of concrete 40mm, target temperature 20℃, target humidity 70%, loading amount 12kg, pre-compaction time 3.5s, vibration frequency 50Hz, and vibration amplitude 0.5mm.

[0047] The automatic detection system is calibrated using standard sand to ensure that the accuracy of pressure sensor 10 and timer 27 meets the requirements. Given that the Vebe time of standard sand is 5 seconds, 5 kg of standard sand is weighed, and the "calibration mode" is clicked. The equipment automatically completes the loading-pre-compaction-vibration-detection process, recording the Vebe time of the system test. If the test value is 4.9s~5.1s (error ≤ ±0.2s), the accuracy of pressure sensor 10 and timer 27 is deemed acceptable. If the error exceeds the tolerance, the pressure sensor sensitivity needs to be adjusted in the "calibration interface" by ±2% for every 0.1s deviation.

[0048] Click "Cavity Control" to start the constant temperature heating film 13 and the atomizing humidification device. Observe the temperature and humidity data inside the constant temperature and humidity detection chamber 4 displayed on the control screen. The system automatically records once every 2 minutes until the temperature stabilizes at the target temperature ±1℃ and the target humidity ±5%. The adjustment of the constant temperature and humidity detection chamber 4 takes about 10 minutes.

[0049] Automatic feeding and pre-compaction Pour the roller-compacted concrete mixture to be tested into the quantitative loading hopper 1. The loading hopper 1 injects the concrete into the testing area of ​​the constant temperature and humidity testing chamber 4 in one go. Click "Loading Start" on the control screen. The solenoid valve at the bottom of the loading hopper 1 will automatically open and start discharging. The pressure sensor 10 will display the weight of the discharged material in real time. When the weight of the discharged material reaches the set value, the equipment will automatically close the solenoid valve, and the control screen will display "Loading Complete". If the control screen prompts "Weight Deviation Exceeds Tolerance" after loading, you need to click "Reload", empty the loading hopper 1, and operate again. After loading is completed, the discharge guide tube will automatically retract upward. After retraction, the control screen will display "Guide Tube in Position".

[0050] Click "Pre-compaction Start". The vibration control unit vibrates according to the set parameters. At the same time, the light sensor 15 is activated to monitor the concrete surface in real time, and the screen displays the image of the concrete surface. During the pre-compaction process, observe the coefficient of variation of the compaction displayed on the control screen. If the coefficient of variation is greater than 2.5% after the set pre-compaction time is reached, the system will automatically extend the vibration time by 0.5s each time, with a maximum extension of 2s, until the coefficient of variation is no greater than 2.5%.

[0051] The light sensor 15 detects whether the concrete surface completely covers the detection area. If it displays "Surface not covered", you need to manually click "Add Material" to open the hopper and add a small amount of concrete, then restart the pre-compaction. After pre-compaction is completed, the vibrator 23 will automatically stop, the control screen will display "Pre-compaction qualified", and it will enter the next waiting state.

[0052] In this embodiment, after the pre-compaction time of 3.5 seconds is reached, the coefficient of variation of compaction is 2.0%, and the "full surface coverage" status is displayed.

[0053] Synchronous linkage detection and data acquisition Clicking "Detection Start" initiates the servo motor-driven automatic lifting and lowering of the material loading cylinder, displaying its position. The pressure-sensing transparent disc 3, driven by a cylinder, automatically descends to a state of contact with the concrete surface but without pressure. The vibrator 23 restarts, beginning vibration at a frequency of 50Hz and an amplitude of 0.5mm. The eight distributed pressure sensors 10 on the pressure-sensing transparent disc 3 work synchronously with the timer 27, displaying pressure data curves on the screen.

[0054] During the automatic lifting of the loading cylinder 2, if the control panel displays "lifting speed deviation", the equipment automatically adjusts the servo motor 8 to increase / decrease the motor current through the PID algorithm to ensure stable speed. During vibration, the displacement sensor monitors the vibration parameters in real time. If the frequency deviation is >±2Hz or the amplitude deviation is >±0.1mm, the control panel alarms "abnormal vibration parameters", and the detection needs to be stopped. Check the frequency converter parameters or the vibrator eccentric block. The light sensor continuously monitors the changes on the concrete surface. If "surface abnormality" is detected, the control panel prompts "re-detection", and the detection area needs to be cleared before re-sampling.

[0055] Intelligent endpoint recognition and timing stop The processor 25 analyzes the data collected by the pressure sensor 10 in real time. When the pressure values ​​of all pressure sensors 10 are ≤0.5N and the screen displays "Pressure stable and up to standard", the vibrator 23 immediately stops vibrating, the timer 26 stops timing, and the screen displays "End point determination, initial VC value".

[0056] In this embodiment, after the pressure stabilizes and meets the target, the screen displays an initial Vebe consistency (VC) value of 2.9s.

[0057] If the test fails to reach the endpoint within 10 seconds, the equipment will alarm "Endpoint Timeout". The fluidity of the concrete needs to be checked and the sample needs to be taken and tested again.

[0058] After the endpoint is determined, the light sensor 15 detects the ambient light intensity inside the constant temperature and humidity testing chamber 4. If the light intensity is <300 lux, the control screen will display "Light intensity not up to standard". After closing the chamber door, click "Retest" to start the synchronous linkage testing process again. After the light intensity meets the standard, the pressure sensor transparent disc 3 will automatically rise and display "Disc reset complete" after rising.

[0059] Error Compensation and Data Output The system automatically calls the data from the humidity sensor 14 and temperature sensor 22 in the constant temperature and humidity detection chamber 4, calculates the temperature and humidity correction coefficient according to (Equation 1), and automatically calculates the final VC value by combining it with the gradation compensation coefficient corresponding to the maximum aggregate size. The screen displays the "final VC value". If you need to manually confirm the compensation coefficient, you can click "View Compensation Parameters" to check whether the temperature, humidity and aggregate coefficients are correct. If there is an error, you can modify the parameters and then click "Recalculate".

[0060] In this embodiment, based on the data from the humidity sensor 14 and temperature sensor 22 inside the constant temperature and humidity detection chamber 4, the initial Vebe consistency (VC) value is corrected using a temperature and humidity correction formula. The measured temperature is 21.4℃ and the measured humidity is 71%. The corrected VC value is then... ’ The value is 2.8s, and the calculation process is as follows: Based on the set maximum aggregate size, the aggregate gradation database is called to correct the difference in vibration resistance caused by coarse aggregate. The compensation coefficient corresponding to the maximum aggregate size of 40mm is 1.04, so the final VC value = 2.85 × 1.04 = 3.0s.

[0061] Results Comparison: The measured VC value using the traditional method is 3.5s, while the VC value in this embodiment is 3.0s. Compared with the designed VC value of 3.0s, the measured result in this embodiment is more consistent with the actual situation.

[0062] Click "Data Output," select the output method, and transmit the final Vebe consistency value, pressure change curve, environmental parameters, and testing time to the terminal. The terminal can automatically generate test records and reports. Click "Data Storage," and the device will locally store the test data, which can be exported via USB flash drive for subsequent quality traceability. In this embodiment, the pressure change curve is as follows: Figure 4 As shown. By Figure 4 It can be seen that the time from pre-compaction to data transmission in this embodiment is approximately 12 seconds.

[0063] After the test, remove the mold and clean the concrete; click "Equipment Reset", the loading cylinder will automatically lower to the lowest position, the pressure sensor transparent disc will rise to the top, the vibrator 23 will reset to the initial angle, the constant temperature and humidity detection chamber 4 will turn off the constant temperature heating film and the atomizing humidity device; turn off the main power of the equipment.

[0064] In addition, regarding the aforementioned C 90 Tests were conducted on the surface of a 20-grade roller-compacted concrete pouring section. Environmental conditions were: temperature 32℃, humidity 55%, and wind speed 5m / s. The specific implementation steps are as follows: The system was moved to the side of the pouring chamber, and the constant temperature and humidity testing chamber was activated. Within 10 minutes, the temperature was adjusted to 20°C and the humidity to 70%. The test was then conducted following the same steps as in the previous embodiment. The initial Vebe consistency (VC) value was found to be 2.8s, with a measured temperature of 20.7°C and a measured humidity of 70%. At this point, the corrected VC value was... ’ The value is 2.8s, and the calculation process is as follows: Based on the set maximum aggregate size, the aggregate gradation database is called to correct the difference in vibration resistance caused by coarse aggregate. The compensation coefficient corresponding to the maximum aggregate size of 40mm is 1.04, so the final VC value is 2.76×1.04=2.9s.

[0065] Results Comparison: The measured VC value using the traditional method was 3.8s, while the VC value in this embodiment was 2.9s. Compared with the designed VC value of 3.0s, the measured results in this embodiment are more consistent with the actual situation.

Claims

1. An automatic detection system for Vebe consistency of roller-compacted concrete, characterized in that... It includes a mechanical execution module, an intelligent control and data acquisition module, and an error compensation module. The mechanical execution module and the intelligent control and data acquisition module are mechanically coupled together.

2. The automatic detection system for Vebe consistency of roller-compacted concrete according to claim 1, characterized in that: The mechanical execution module includes a quantitative feeding unit, a synchronous linkage execution unit, and a vibration control unit; The quantitative feeding unit includes a feeding hopper (1) with adjustable volume. The synchronous linkage execution unit includes an automatic lifting loading cylinder (2), a pressure sensing transparent disc (3), and a constant temperature and humidity detection chamber (4). The automatic lifting loading cylinder (2) is installed inside the constant temperature and humidity detection chamber (4). A vertical slide rail (5) is provided on each side of the automatic lifting loading cylinder (2). A slider (6) is configured on the slide rail (5). A displacement sensor is configured on the slider (6). The automatic lifting loading cylinder (2) is installed on the slide rail (5) through the slider (6). The slider (6) is connected to a screw drive device (7). The screw drive device (7) is connected to a servo motor (8). The automatic lifting loading cylinder (2) is matched and installed with the loading hopper (1). The pressure sensing transparent disc (3) includes a transparent disc body (9) and pressure sensors (10) evenly distributed at the bottom of the disc body (9). The disc body (9) has a sealed groove (11) for cable routing inside. The edge of the disc body (9) has a junction box (12) for connecting the cable. The pressure sensor (10) is connected to the intelligent control and data acquisition module via the junction box (12) using a shielded cable. The constant temperature and humidity detection chamber (4) is equipped with a constant temperature heating film (13), a humidity sensor (14), a temperature sensor (22) and a light sensor (15). The constant temperature heating film (13) is composed of a high temperature resistant polyester film (16) and a resistance wire (17) inside the polyester film. The resistance wire (17) is connected to a temperature and humidity controller (18) through a wire. The temperature sensor (22) is connected to the temperature and humidity controller (18). The constant temperature and humidity detection chamber (4) is equipped with an atomizing humidity device on the top. The atomizing humidity device includes an ultrasonic atomizer (20), a nozzle (21) and a water tank (28). The nozzle (21) is installed around the top of the constant temperature and humidity detection chamber (4). The humidity sensor (14) is connected to the temperature and humidity controller (18). The vibration control unit includes a vibrator (23) and a motor controller (24). The vibrator (23) is fixedly connected to the bottom of the constant temperature and humidity testing chamber (4) through a shock-absorbing rubber pad (25). The vibrator (23) is a vibration motor, and the vibration motor is connected to the motor controller (24) through a power cord.

3. The automatic detection system for Vebe consistency of roller-compacted concrete according to claim 2, characterized in that: The intelligent control and data acquisition module includes a processor (26), a timer (27), a humidity sensor (14), a temperature sensor (22), and a wireless transmission unit; The processor (26) is located in the control box on the side of the constant temperature and humidity detection chamber (4), and is responsible for receiving data from each sensor, controlling the actions of each actuator, and coordinating the timing of the entire detection process. The processor (26) communicates with the timer (27), pressure sensor (10), humidity sensor (14), and temperature sensor (22) wireless transmission units via a data bus to achieve rapid data transmission and processing; The timer (27) is integrated on the circuit board of the processor (26); The temperature sensor (14) and humidity sensor (22) are synchronously arranged at the top and middle of the constant temperature and humidity detection chamber (4) to collect temperature and humidity environmental parameters inside the constant temperature and humidity detection chamber (4); The wireless transmission unit interacts with the processor (26) via serial communication, and the wireless transmission unit connects to the terminal device using a Bluetooth or 4G module.

4. The automatic detection system for Vebe consistency of roller-compacted concrete according to claim 3, characterized in that: The error compensation module incorporates temperature and humidity compensation algorithms, aggregate gradation compensation algorithms, and data anomaly removal algorithms to dynamically correct detection errors.

5. An automatic detection method for Vebe consistency of roller-compacted concrete according to claim 4, characterized in that: Includes the following steps: S1: Device initialization and parameter settings; S2: Automatic loading and pre-compaction; S3: Synchronous linkage detection and data acquisition; S4: Intelligent endpoint recognition and timer stop; S5: Error Compensation and Data Output.

6. The automatic detection method for Vebe consistency of roller-compacted concrete according to claim 5, characterized in that: In step S1, the device initialization and parameter setting include the following steps: a1. Start the automatic detection system and set the detection parameters through the intelligent control and data acquisition module. The detection parameters include the maximum particle size of concrete aggregate, target temperature, target humidity, loading amount, pre-compaction time, vibration frequency and vibration amplitude information. a2. Calibrate the automatic detection system using standard sand with known Vebe time.

7. The automatic detection method for Vebe consistency of roller-compacted concrete according to claim 6, characterized in that: In step S2, the automatic loading and pre-compaction includes the following steps: b1. Pour the roller-compacted concrete mixture to be tested into the hopper (1), and the hopper (1) injects the concrete into the testing area of ​​the constant temperature and humidity testing chamber (4) in one go; b2. Start the vibration control unit and use the vibrator (23) to pre-compact the concrete by vibration; b3. Detect whether the concrete surface is completely covered by the light sensor (15). If it is not completely covered, return to step b2 to continue oscillation pre-compaction. If it is completely covered, proceed to step S3.

8. The automatic detection method for Vebe consistency of roller-compacted concrete according to claim 5, characterized in that: In step S3, the synchronous linkage detection and data acquisition includes the following steps: c1. The servo motor (8) drives the automatic lifting loading cylinder (2) to rise upwards, and the pressure sensing transparent disc (3) automatically descends to fit the concrete surface. The automatic lifting loading cylinder (2), the pressure sensing transparent disc (3) and the center of the detection area coincide. c2. Start the vibrator (23), and the vibrator (23) will start vibrating according to the set parameters; c3. The pressure sensor (10) of the pressure sensing transparent disk (3) works synchronously with the timer (27) to collect pressure data and time data and transmit them to the processor (26) in real time. c4. Monitor the changes on the concrete surface in real time using a light sensor (15). If a significant change is detected on the concrete surface, return to step c1 and re-detect.

9. The automatic detection method for Vebe consistency of roller-compacted concrete according to claim 8, characterized in that: In step S4, the intelligent endpoint recognition and timing stop includes the following steps: d1. The processor (26) analyzes the data collected by the pressure sensor (10) in real time. When the pressure value of all pressure sensors (10) is ≤0.5N, it is determined that the pressure sensing transparent disc (3) is completely supported by concrete and there is no obvious gap. The vibrator (23) is immediately controlled to stop vibrating and the timer (27) is stopped. At this time, the time displayed by the timer (27) is the initial time of the initial Vebe consistency VC value, which is t0. d2. Use the light sensor (15) to confirm whether the ambient light intensity around the detection area is within the preset range. If it is not within the preset range, return to step c1 to re-detect.

10. The automatic detection method for Vebe consistency of roller-compacted concrete according to claim 6, characterized in that: In step S5, the error compensation and data output include the following steps: e1. The error compensation module calls the temperature and humidity compensation algorithm, aggregate gradation compensation algorithm, and data anomaly removal algorithm to dynamically correct the detection error and correct the initial Vebe consistency (VC) value; e2. Temperature and humidity compensation: Based on the data from the humidity sensor (14) and temperature sensor (22) inside the constant temperature and humidity detection chamber (4), the temperature and humidity correction formula is used for correction; e3. Aggregate gradation compensation: Based on the maximum aggregate size set in step a1, the aggregate gradation database is called to correct the difference in vibration resistance caused by coarse aggregate; e4. Data anomaly removal: Through pressure change curve smoothness analysis, outlier data with single pressure fluctuations >5N are removed, and the result is optimized by using the average of 5 adjacent valid data sets; e5. The final Vebe consistency value, pressure change curve, environmental parameters, and detection time data are transmitted to the terminal via the wireless transmission unit, and the terminal device automatically generates detection records and reports.

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