[0018] The present invention will be further described in detail below in conjunction with the drawings:
[0019] reference figure 1 The test device for testing the shear failure of asphalt pavement according to the present invention includes a control system, a test stand 24, a reaction stand on the test stand 24, and a temperature control box 1, a sample bearing platform for placing the sample 6 to be tested 4. Wheel 15 located on the sample 6 to be tested, a lateral drive device for driving the wheel 15 to move on the surface of the sample 6 to be tested, and a vertical force applied to the wheel 15 to exert pressure on the surface of the sample 6 to be tested Device, a displacement sensor 22 for detecting the horizontal displacement of the surface of the sample 6 to be tested, a lateral pressure sensor 21 for detecting the thrust of the lateral drive device on the wheel 15 and a sensor for detecting the pressure exerted on the surface of the sample 6 by the wheel 15 The vertical pressure sensor 19 exerts a reverse force on the lateral drive device and the vertical force device through the reaction frame, and the sample bearing table 4, wheels 15 and the sample 6 to be tested are located in the temperature control box 1, and the control system and The control end of the lateral drive device, the control end of the vertical force device, the output end of the displacement sensor 22, the output end of the lateral pressure sensor 21 and the output end of the vertical pressure sensor 19 are connected, and the outer circumference of the wheel 15 is wrapped with a rubber layer .
[0020] The reaction frame includes a first vertical reaction beam 2, a second vertical reaction beam, and a lateral reaction beam 3, wherein the first vertical reaction beam 2 and the second vertical reaction beam are both vertical Fixed on the test stand 24, the two ends of the transverse reaction beam 3 are respectively connected with the upper end of the first vertical reaction beam 2 and the upper end of the second vertical reaction beam.
[0021] It also includes a transmission system. The transmission system includes a pulley 18, a force transmission box 17, and a connecting fork 16. The vertical force application device includes a vertical force force shaft 7 and a vertical force force head 8 located in the temperature control box 1. Among them, the upper end of the vertical afterburner shaft 7 is fixed on the lateral reaction frame, and the lower end of the vertical afterburner shaft 7 is inserted into the temperature control box 1 and then fixed on the vertical afterburner 8. The vertical afterburner The bottom of 8 is provided with a sliding groove 10 that is matched with the pulley 18, the pulley 18 is fixed to the top of the power transmission box 17 through a connecting shaft, the upper end of the connecting fork 16 is fixed to the bottom of the power transmission box 17, and the wheel 15 is axially connected to the connecting fork 16 is at the lower end, and the vertical pressure sensor 19 is located at the middle position of the connecting fork 16, the control end of the vertical afterburner shaft 7 is connected with the control system; the connecting fork 16 is provided with a rotation limiter 23 for restricting the rotation of the wheel 15 .
[0022] The transverse drive device includes a transverse force spring 14, a holder 20, a transverse push shaft 11, and a transverse push head 12 and a transverse push head 13 located in the temperature control box 1, wherein the transverse push shaft 11 One end is fixed to the first vertical reaction beam 2, the other end of the transverse pushing shaft 11 passes through the side of the temperature control box 1 and is connected to the transverse pushing head 12, and one end of the transverse pushing spring 14 is fixed to the second On the vertical reaction beam, the other end of the transverse force spring 14 passes through the side surface of the temperature control box 1 and is connected to the transverse force indenter 13, wherein the transverse thrust indenter 12, the transverse force indenter 13 and the transmission The force box 17 is located on the same straight line, and the transverse push head 12 pushes the force transfer box 17 so that the force transfer box 17 contacts the transverse force press head 13 and compresses the transverse force spring 14, which is passed through the transverse force The force pressure head 13 pushes the force transmission box 17 to move horizontally, and the control end of the lateral push shaft 11 is connected to the control system; the lateral pressure sensor 21 is located between the lateral force spring 14 and the second vertical reaction beam; the retainer 20 The upper end is connected to the transverse reaction beam 3 and can move on the transverse reaction beam 3. When the transverse force spring is compressed, move the holder 20 to a position aligned with the middle of the force transmission box 17, and the holder 20 The upper end is fixed on the transverse reaction beam 3, and the lower end of the fixer 20 is fixed on the side of the force transmission box 17. In addition, the lower end of the holder 20 can be controlled to be disconnected from the side of the force transmission box 17 during the test.
[0023] The two ends of the chute 10 are provided with stoppers 9 for restricting the pulley 18; the height of the sample bearing platform 4 can be adjusted according to the thickness of the sample 6 to be tested, the sample bearing platform 4 and the sample 6 to be tested An adhesive layer 5 is provided between.
[0024] When working, the force transmission box 17 is pushed through the lateral pushing shaft 11 and the lateral pushing head 12 to compress the lateral force spring 14. When the force transmission box 17 moves to a certain pressure position, the lower end of the holder 20 is controlled to be transmitted The side of the force box 17 is fixed; the horizontal pushing shaft 11 and the horizontal pushing head 12 are controlled to move to the leftmost position, and pressure is applied to the vertical afterburner 8 through the vertical afterburner shaft 7, and the vertical afterburner presses The head 8 applies vertical pressure to the test specimen 6 through the force transmission box 17, the connecting fork 16 and the wheels 15; when the wheels 15 are required to travel, the force transmission box 17 is automatically disconnected from the holder 20, and the lateral force spring 14 pushes The force transmission box 17 moves, so that the wheels 15 slide at a reduced speed on the sample 6 to be tested.
[0025] The specific test process of the present invention is:
[0026] 1. Destruction of unconfined asphalt mixture specimen
[0027] 1a) Initialize the test device to eliminate the influence of friction between pulley 18 and chute 10 on the test;
[0028] 1b) Stick the sample 6 to be tested on the sample bearing platform 4, and fix the displacement sensor 22 on the left side of the upper surface of the sample 6 to be tested, and adjust the initial displacement of the displacement sensor 22 to s 1 , Then adjust the temperature of the temperature control box 1 to T;
[0029] 1c) The lateral pushing head 12 is moved to the far left end, and then the vertical forcing shaft 7 is controlled to move down, so that the wheel 15 generates vertical pressure on the test specimen 6. During the test, the wheel 15 is applied by the limiter 23 Fix it and keep the wheel 15 constant at the vertical pressure of the sample 6 to be tested;
[0030] 1d) Disconnect the retainer 20, and the transverse force spring 14 pushes the force transmission box 17, so that the wheel 15 moves to the left at a certain initial speed until it stops;
[0031] 1e) When the wheel 15 stops, the displacement sensor 22 reads the displacement as s 2 In this process, the shear slip rate is used as the failure judgment index of the unconfined asphalt mixture specimen. When the shear slip rate exceeds the preset value, the sample 6 to be tested is considered to be damaged, where the shear slip rate p for:
[0032]
[0033] Δs=s 2 -s 1 , H is the height of the sample 6 to be tested.
[0034] 1f) Adjust the vertical pressure and horizontal force of the wheel 15, compare the relationship between the shear slip rate obtained in the test and the given shear slip rate, and then the maximum vertical pressure and maximum horizontal force can be obtained when a test wave breaks. ; At the same time, steps 1d) and 1e) can be repeated to obtain the fatigue vertical pressure, fatigue horizontal force and fatigue action times during multiple test failures.
[0035] 2. Destruction of confined asphalt mixture specimens, the specific operation process is:
[0036] 2a) Initialize the test device to eliminate the influence of the friction between the pulley 18 and the chute 10 on the test;
[0037] 2b) Fix the sample 6 to be tested on the sample bearing platform 4, cover the four sides of the sample 6 to be tested with a test mold with the same height as the sample 6 to be tested, and then adjust the temperature of the temperature control box 1 to T;
[0038] 2c) Repeat steps 1c) and 1d). In this process, the maximum vertical displacement difference is used as the criterion for determining the damage of the confined asphalt mixture specimen. When the maximum vertical displacement difference exceeds the preset value, the specimen is considered to be damaged. The maximum displacement difference Δδ is:
[0039] Δδ=δ 1 -δ 2
[0040] Where δ 1 Is the maximum vertical displacement of the upper surface of the specimen, δ 2 Is the maximum vertical displacement downward from the upper surface of the test piece;
[0041] 2d) Continuously adjust the vertical pressure and horizontal force through the control system, compare the relationship between the maximum vertical displacement difference obtained in the test and the maximum given vertical displacement difference, and then the maximum vertical pressure and maximum horizontal force can be obtained when a test fails , The fatigue vertical pressure and fatigue horizontal force and the number of fatigue actions can also be obtained during multiple test failures.
