A device for detecting dynamic fatigue strength of a tail brush of a shield

Abstract

The utility model relates to shield tail brush detection technical field, especially shield tail brush dynamic fatigue strength detection device. It includes experimental board material, transparent board material, lifting mechanism, support frame, shield tail brush, shield tail brush support, transverse drive mechanism, controller, sensor, data acquisition and analysis module, transparent board material is fixed below support frame top, experimental board material is placed below the space surrounded by transparent board material and constitutes grease cavity together, is equipped with the grease injection hole on transparent board material, experimental board material connects lifting mechanism, transverse drive mechanism is installed in support frame and is connected shield tail brush support, shield tail brush is connected on shield tail brush support and contacts experimental board material, controller connects lifting mechanism and transverse drive mechanism, sensor is installed below shield tail brush support, and data acquisition and analysis module obtains sensor data. The device simulates the repeated movement of shield tail brush transversely and longitudinally, and simulates the working condition of shield tail brush and grease together, and is more close to actual engineering.

Description

Technical Field

[0001] This utility model relates to the field of shield tail brush detection technology, and in particular to a device for detecting the dynamic fatigue strength of shield tail brush. Background Technology

[0002] With the increasingly widespread application of tunnel boring machines (TBMs), the tail brush, as a core sealing component of the TBM, directly affects engineering safety and construction efficiency due to its dynamic fatigue strength. Installed at the tail of the TBM, the tail brush seals the annular gap between the shield and tunnel segments, preventing the infiltration of groundwater and mud. It also withstands earth pressure, water pressure, dynamic friction during TBM advancement, and the compression of the tunnel segments. Insufficient fatigue strength of the tail brush can lead to seal failure, water and sand inrush, ground subsidence, and even collapse, resulting in extremely high repair costs. Therefore, a device is needed to simulate the problems encountered in actual engineering projects and conduct fatigue strength testing on the tail brush. Utility Model Content

[0003] This invention provides a dynamic fatigue strength testing device for shield tail brushes, aiming to solve the problem of the existing need for simulation technology engineering teams to test shield tail brushes.

[0004] This utility model provides a dynamic fatigue strength testing device for a shield tail brush, including a test plate, a transparent plate, a lifting mechanism, a support frame, a shield tail brush, a shield tail brush support, a lateral drive mechanism, a controller, a sensor, and a data acquisition and analysis module. The transparent plate is fixed below the top of the support frame, and the test plate is placed below the space enclosed by the transparent plate. The transparent plate and the test plate together form a grease chamber. The transparent plate has grease injection holes. The test plate is connected to the lifting mechanism. The lateral drive mechanism is installed on the top of the support frame and is connected to and drives the shield tail brush support. The shield tail brush is connected to the shield tail brush bracket, and the end of the shield tail brush contacts the test plate. The shield tail brush and the shield tail brush support are located inside the grease chamber. The controller is connected to and controls the lifting mechanism and the lateral drive mechanism. A sensor placement area is connected below the shield tail brush support, and the sensor is installed in the sensor placement area. The data acquisition and analysis module acquires data from the sensor.

[0005] As a further improvement of this utility model, the lifting mechanism includes an electric telescopic hydraulic rod, a hydraulic cylinder, a hydraulic motor, and a plate clamp. The bottom of the electric telescopic hydraulic rod is connected to a hydraulic rod, and the top of the electric telescopic hydraulic rod is connected to the experimental plate through the plate clamp. The hydraulic motor is connected to and drives the hydraulic cylinder, and the controller is connected to and controls the hydraulic motor.

[0006] As a further improvement of this utility model, the transverse drive mechanism includes a guide rail motor and an electric guide rail. The electric guide rail is installed below the top of the support frame and is located within the grease chamber. The shield tail brush bracket is slidably connected to the electric guide rail. The guide rail motor is connected to and drives the electric guide rail. The controller is connected to and controls the guide rail motor through wires.

[0007] As a further improvement of this utility model, the bottom of the shield tail brush support is provided with a shield tail brush protection plate, and the sensor placement area is detachably connected to the bottom of the shield tail brush support and to the side near the shield tail brush protection plate.

[0008] As a further improvement of this utility model, the sensor includes an acoustic emission sensor and a pressure sensor. The acoustic emission sensor is installed in the sensor placement area near the tail brush and is used to receive the elastic signal released by the tail brush due to fatigue failure and cracks. The pressure sensor is installed at the bottom of the sensor placement area and is used to monitor the elastic force generated by the tail brush.

[0009] As a further improvement of this utility model, the data acquisition and analysis module includes: a data acquisition instrument, used to collect the elastic signals collected by the acoustic emission sensor and the pressure sensor and the elastic force value of the shield tail brush; computer software, connected to the data acquisition instrument, used to set data acquisition parameters, and to display, store, and subsequently analyze and plot the acquired data in real time; and a signal conditioner, used to amplify, filter, and process the sensor signals.

[0010] As a further improvement of this utility model, the support frame includes a column and a bracket, the bracket is connected to the top of the column, the bracket is provided with a slot or hollow space for installing a transverse drive mechanism below the bracket, the transparent material is connected to the bottom of the bracket, and the controller is installed on the column.

[0011] As a further improvement of this utility model, the controller controls the shield tail brush to perform lateral reciprocating motion relative to the experimental plate through a lateral drive mechanism, so as to simulate the lateral friction between the tube segment and the shield tail brush.

[0012] As a further improvement of this utility model, the control is to control the experimental plate to move longitudinally back and forth relative to the shield tail brush or to fix it in a certain position through the lifting mechanism, so as to simulate the fatigue damage caused by the shield tail brush being repeatedly squeezed by the pipe segments in the engineering.

[0013] The beneficial effects of this utility model are: by combining the lateral drive mechanism and the lifting mechanism, the repeated lateral and longitudinal movements of the shield tail brush are simulated, and the working situation of the shield tail brush and grease is simulated, which is more in line with actual engineering; at the same time, the location and development law of crack initiation generated by the shield tail brush during fatigue failure are explored by using sensors, which more completely simulates and detects the fatigue problems encountered by the shield tail brush in engineering. Attached Figure Description

[0014] Figure 1 This is an overall structural diagram of the dynamic fatigue strength testing device for the shield tail brush of this utility model; Figure 2 This is a cross-sectional view of the sensor placement area in this utility model.

[0015] The diagram shows the component names and their corresponding markings: 1. Electric telescopic hydraulic rod; 2. Hydraulic cylinder; 3. Hydraulic motor; 4. Experimental board; 5. Tempered glass; 6. Shield tail brush; 7. Shield tail brush support; 8. Fixing bolt; 9. Grease injection hole; 10. Electric guide rail; 11. Guide rail motor; 12. Bracket; 13. Wire; 14. Controller; 15. Grease chamber; 16. Support column; 17. Sensor placement area; 18. Board clamp; 19. Computer software; 20. Data acquisition instrument; 21. Signal conditioner; 22. Pressure sensor; 23. Acoustic emission sensor; 24. Bolt. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0017] like Figure 1 As shown, this utility model discloses a dynamic fatigue strength testing device for a shield tail brush, comprising an experimental plate 4, a transparent plate, a lifting mechanism, a support frame, a shield tail brush 6, a shield tail brush support 7, a lateral drive mechanism, a controller 14, a sensor, and a data acquisition and analysis module. The transparent plate is fixed below the top of the support frame, and the experimental plate 4 is placed below the space enclosed by the transparent plate. The transparent plate and the experimental plate 4 together constitute a grease chamber 15. The transparent plate is provided with a grease injection hole 9. The experimental plate 4 is connected to the lifting mechanism. The lateral drive mechanism is installed on the top of the support frame and is connected to and drives the shield tail brush support 7. The shield tail brush 6 is connected to the shield tail brush support 7, and the end of the shield tail brush 6 contacts the experimental plate 4. The shield tail brush 6 and the shield tail brush support 7 are located in the grease chamber 15. The controller 14 is connected to and controls the lifting mechanism and the lateral drive mechanism. A sensor placement area 17 is connected below the shield tail brush support 7, and the sensor is installed in the sensor placement area 17. The data acquisition and analysis module acquires the data from the sensor.

[0018] The transparent plate is made of tempered glass 5, allowing for direct observation of the actual condition of the shield tail brush 6 and grease within the grease chamber 15. The tempered glass 5 is fixed to the top bracket 12 with bolts, forming a cuboid that, together with the experimental plate 4 below, forms the grease chamber 15, simulating the working environment of pipe segments, grease, and pipe segments in engineering. The shield tail brush 6 is fixed to the shield tail brush support 7 with fixing bolts 8 to prevent it from falling off due to pressure from the experimental plate 4. Once the experimental plate 4 is ready, grease is injected into the grease chamber 15 through the grease injection hole 9 to work with the shield tail brush 6, simulating fatigue failure of the shield tail brush when it works simultaneously with the grease. After the experiment, the experimental plate 4 and tempered glass 5 can be removed to disassemble and clean the shield tail brush 6 and remove the grease for the next test.

[0019] The lifting mechanism includes an electric telescopic hydraulic rod 1, a hydraulic cylinder 2, a hydraulic motor 3, and a plate clamp 18. The bottom of the electric telescopic hydraulic rod 1 is connected to the hydraulic rod 2, and the top of the electric telescopic hydraulic rod 1 is connected to the experimental plate 4 through the plate clamp 18. The hydraulic motor 3 is connected to and drives the hydraulic cylinder 2, and the controller 14 is connected to and controls the hydraulic motor 3.

[0020] The controller 14 controls the experimental plate 4 to move longitudinally back and forth relative to the shield tail brush 6 or to fix it in a certain position through the lifting mechanism, so as to simulate the fatigue failure caused by the shield tail brush 6 being repeatedly squeezed by the pipe segments in the project.

[0021] The electric telescopic hydraulic rod 1, hydraulic cylinder 2, and hydraulic motor 3 work together to control the up-and-down reciprocating motion of the experimental plate 4; the plate clamp 18 is used to connect the experimental plate 4 and the electric telescopic hydraulic rod 1.

[0022] After the experimental plate 4 is fixed by the plate clamp 18, the experimental plate 4 is driven to move longitudinally up and down by the electric telescopic hydraulic rod 1. It can also be fixed in the same position, so that only the damage of lateral friction to the fatigue strength of the shield tail brush 6 can be investigated. Furthermore, the experimental plate 4 can be replaced with different materials as needed.

[0023] Specifically, the controller 14 controls the hydraulic device motor 3 to drive the hydraulic cylinder 2 to move longitudinally, thereby causing the plate clamp 18 connected to the electric telescopic hydraulic rod 1 to move the experimental plate 4. According to the experimental needs, the controller 14 can control the experimental plate 4 to perform longitudinal reciprocating motion or fix it in a certain position, thereby simulating the fatigue failure caused by the shield tail brush 6 being repeatedly squeezed by the tunnel lining segments in engineering.

[0024] The lateral drive mechanism includes a guide rail motor 11 and an electric guide rail 10. The electric guide rail 10 is installed below the top of the support frame and is located within the grease chamber 15. The shield tail brush bracket 7 is slidably connected to the electric guide rail 10. The guide rail motor 11 is connected to and drives the electric guide rail 10. The controller 14 is connected to and controls the guide rail motor 11 through the wire 13.

[0025] The controller 14 controls the shield tail brush to reciprocate laterally relative to the experimental plate 4 through the lateral drive mechanism to simulate the lateral friction between the tube segment and the shield tail brush 6.

[0026] The guide rail motor 11 is installed in the top bracket 12 and drives the electric guide rail 10 to control the shield tail brush support 7 to move laterally, so as to simulate the lateral friction between the tube segment and the shield tail brush 6. The electric guide rail 10 is installed below the top bracket 12 and the shield tail brush support 7 can slide on its track.

[0027] Specifically, the electric guide rail 10 is installed in the groove below the top bracket 12 and fixed with bolts. The guide rail motor 11 and the wire 13 are placed in the hollow part of the top bracket 12. The electric guide rail 10 drives the guide rail motor 11 connected to it through the controller 14 to control the transverse movement of the shield tail brush support 7. The guide rail motor 11 can control its reciprocating motion, thereby driving the shield tail brush 6 to rub against the experimental plate 4 to simulate the friction condition between the shield tail brush 6 and the experimental plate 4.

[0028] The controller 14 controls the hydraulic device motor 3 and the guide rail motor 11 respectively through the wire 13. It is equipped with a display and can set the movement speed and direction to achieve the purpose of controlling the reciprocating motion of the experimental plate 4 and the shield tail brush 6.

[0029] The bottom of the shield tail brush support 7 is provided with a shield tail brush protection plate, and the sensor placement area 17 is detachably connected to the bottom of the shield tail brush support 7 and to the side near the shield tail brush protection plate.

[0030] The sensor placement area 17 is fixed to the bottom of the shield tail brush support 7 by fixing bolts 24, near the shield tail brush protection plate. It can be disassembled and the required sensors can be added independently according to the needs of subsequent experiments.

[0031] like Figure 2 As shown, the sensor includes an acoustic emission sensor 23 and a pressure sensor 22. The acoustic emission sensor 23 and the pressure sensor 22 are arranged in the sensor placement area 17. The acoustic emission sensor 23 is installed on the side of the sensor placement area near the tail brush 6 and is used to receive the elastic signal released by the cracks generated by the fatigue failure of the tail brush 6. The pressure sensor 22 is installed at the bottom of the sensor placement area 17 and is used to monitor the elastic force generated by the tail brush 6.

[0032] The sensor placement area 17 contains an acoustic emission sensor 23 and a pressure sensor 22. It is a cuboid made of acrylic sheet to reduce the impact of elastic signals released by other metals on the experiment.

[0033] The data acquisition and analysis module includes: a data acquisition unit 20, used to collect elastic signals and elastic force values ​​of the tail brush from acoustic emission sensors and pressure sensors; computer software 19, connected to the data acquisition unit, used to set data acquisition parameters, and to display, store, and subsequently analyze and plot the acquired data in real time; and a signal conditioner 21, used to amplify and filter sensor signals to improve signal quality. Finally, by studying the data, the dynamic fatigue strength and damage of the tail brush 6 are obtained, its crack initiation is located, and its development law is analyzed.

[0034] Under cyclic loading, the tail brush 6 will generate micro-cracks. When the cracks propagate, they will release elastic wave acoustic emission signals. These signals are captured by the acoustic emission sensor 23. These signals are processed and analyzed by the data acquisition and analysis device and computer software 19, and combined with the data obtained by the pressure sensor 22 to verify the fatigue mechanism of the tail brush from multiple dimensions and analyze the crack development law.

[0035] The support frame includes a column 16 and a bracket 12. The bracket is connected to the top of the column. The bracket 12 has a slot or hollow space below it for installing a horizontal drive mechanism. A transparent material is connected below the bracket 12. The controller 14 is installed on the column 16. The column 16 and the top bracket 12 are made of aluminum alloy for easy reinforcement and handling. The bottom of the top bracket 12 has a groove for installing the electric guide rail 10, and the hollow interior is used to house the guide rail motor 11 and the connecting wires 13.

[0036] The testing process of this shield tail brush dynamic fatigue strength testing device includes the following steps: S1: Fix the tail brush 6 to the tail brush support 7 using fixing bolts 8, and place the protective plate side close to the sensor placement area 17. Fix the experimental plate 4 using the plate clamp 18, then use bolts to fix the tempered glass 5 below the top bracket 12, and place the experimental plate 4 below the space enclosed by the tempered glass 5. Use the controller 14 to raise the experimental plate 4 to the height of the bottom of the tempered glass 5.

[0037] S2: According to the experimental requirements, different types of grease are injected into the grease chamber 15 through the grease injection hole 9 and tested together with the shield tail brush 6.

[0038] S3: According to the experimental requirements, the controller 14 drives the guide rail motor 11, so that the experimental plate 4 and the shield tail brush 6 reciprocate at a certain speed.

[0039] S4: Start the controller 14 switch to begin the fatigue test. The data acquisition instrument 20 and the computer software 19 can collect and analyze the data of the emission sensor 23 and pressure sensor 22 installed in the sensor placement area 17, thereby determining the crack source and crack development status caused by fatigue failure of the shield tail brush, as well as the elasticity value of the shield tail brush 6 during the process.

[0040] S5: After the experiment, lower the experimental plate 4 and remove it, take off the tempered glass 5 and the tail brush 6, and clean the instrument.

[0041] S6: Repeat the above steps and conduct the next experiment.

[0042] This invention simulates repetitive lateral and longitudinal movements by combining an electric telescopic hydraulic rod 1 and an electric guide rail 10, and also simulates the working conditions of the tail brush 6 and grease, thus better reflecting actual engineering practices. This device can more comprehensively simulate the fatigue problems encountered by the tail brush 6 in engineering projects, using a combination of acoustic emission sensor 23 and pressure sensor 22 to investigate the location and development pattern of crack initiation during fatigue failure of the tail brush 6. This device can predict the service life of the tail brush 6, detect potential fatigue damage, and ensure the smooth operation of the tunnel boring machine.

[0043] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. A device for detecting the dynamic fatigue strength of a shield tail brush, characterized in that, The device includes an experimental plate, a transparent plate, a lifting mechanism, a support frame, a shield tail brush, a shield tail brush support, a lateral drive mechanism, a controller, sensors, and a data acquisition and analysis module. The transparent plate is fixed below the top of the support frame, and the experimental plate is placed below the space enclosed by the transparent plate. The transparent plate and the experimental plate together form a grease chamber. The transparent plate has grease injection holes. The experimental plate is connected to the lifting mechanism. The lateral drive mechanism is installed on the top of the support frame and is connected to and drives the shield tail brush support. The shield tail brush is connected to the shield tail brush bracket, and the end of the shield tail brush contacts the experimental plate. The shield tail brush and the shield tail brush support are located inside the grease chamber. The controller connects to and controls the lifting mechanism and the lateral drive mechanism. A sensor placement area is connected below the shield tail brush support, and the sensors are installed in the sensor placement area. The data acquisition and analysis module acquires data from the sensors.

2. The shield tail brush dynamic fatigue strength testing device according to claim 1, characterized in that, The lifting mechanism includes an electric telescopic hydraulic rod, a hydraulic cylinder, a hydraulic motor, and a plate clamp. The bottom of the electric telescopic hydraulic rod is connected to a hydraulic rod, and the top of the electric telescopic hydraulic rod is connected to the experimental plate through the plate clamp. The hydraulic motor is connected to and drives the hydraulic cylinder, and the controller is connected to and controls the hydraulic motor.

3. The dynamic fatigue strength testing device for shield tail brush according to claim 1, characterized in that, The lateral drive mechanism includes a guide rail motor and an electric guide rail. The electric guide rail is installed below the top of the support frame and is located within the grease chamber. The shield tail brush bracket is slidably connected to the electric guide rail. The guide rail motor is connected to and drives the electric guide rail. The controller is connected to and controls the guide rail motor via wires.

4. The dynamic fatigue strength testing device for shield tail brush according to claim 1, characterized in that, The bottom of the shield tail brush support is provided with a shield tail brush protection plate, and the sensor placement area is detachably connected to the bottom of the shield tail brush support and to the side near the shield tail brush protection plate.

5. The shield tail brush dynamic fatigue strength testing device according to claim 1, characterized in that, The sensors include an acoustic emission sensor and a pressure sensor. The acoustic emission sensor is installed in the sensor placement area near the tail brush and is used to receive the elastic signal released by the tail brush due to fatigue failure and cracks. The pressure sensor is installed at the bottom of the sensor placement area and is used to monitor the elastic force generated by the tail brush.

6. The shield tail brush dynamic fatigue strength testing device according to claim 5, characterized in that, The data acquisition and analysis module includes: a data acquisition instrument for collecting elastic signals and elastic force values ​​from the acoustic emission sensor, pressure sensor, and tail brush; computer software connected to the data acquisition instrument for setting data acquisition parameters, real-time display, storage, and subsequent analysis and plotting of the acquired data; and a signal conditioner for amplifying, filtering, and other processing of the sensor signals.

7. The dynamic fatigue strength testing device for shield tail brush according to claim 1, characterized in that, The support frame includes a column and a bracket. The bracket is connected to the top of the column. The bracket has a slot or hollow space below it for installing a lateral drive mechanism. The transparent material is connected to the bottom of the bracket. The controller is installed on the column.

8. The shield tail brush dynamic fatigue strength testing device according to claim 1, characterized in that, The controller controls the tail brush to reciprocate laterally relative to the experimental plate through a lateral drive mechanism to simulate the lateral friction between the tube segment and the tail brush.

9. The dynamic fatigue strength testing device for shield tail brush according to claim 1, characterized in that, The control system uses a lifting mechanism to control the experimental plate to move longitudinally back and forth relative to the tail shield brush or to fix it in a certain position, thereby simulating the fatigue damage caused by the tail shield brush being repeatedly squeezed by the tunnel lining segments in engineering.

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