Simulation loading test device suitable for cross-creep fault tunnel

Abstract

The utility model discloses a simulation loading test device suitable for a cross-creeping fault tunnel, and aims to solve the problem that most of existing indoor simulation loading devices for the cross-creeping fault tunnel are mainly based on a stick-slip fault and can only be used for test research on the aspects of damage mechanism and prevention and control of a tunnel structure caused by the stick-slip fault. The utility model aims at carrying out research on the interaction mechanism between the creep fault and the tunnel structure, catastrophe prevention and control and monitoring and early warning aspects through indoor test simulation. Free contraction and shear deformation of the fixed model box and the movable model box are achieved through the spring and the telescopic connecting belt, and shear dislocation simulation of the creep fault crossing tunnel is achieved. And dislocation loading of the movable model box can be realized through a second jack and a third jack which can move freely.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of geotechnical test device, concretely relates to a kind of simulation loading test device suitable for across creep fault tunnel. BACKGROUND

[0002] A large number of tunnel construction projects in western mountainous areas often inevitably cross active fault areas, which adds great difficulty to tunnel construction. The adverse effects of faults on mountainous tunnels mainly manifest as follows: on the one hand, the existence of active faults will have adverse effects on the stress field of mountainous areas, specifically, stress redistribution effect will cause the original stress state of surrounding rock to be destroyed, resulting in stress concentration of surrounding rock, which is the root cause of tunnel structure damage or surrounding rock instability; on the other hand, tunnel excavation induces fault activation, which leads to a significant reduction in the strength of surrounding rock, and further adversely affects the tunnel lining. If the fault area is not pre-strengthened before construction, tunnel excavation and post-completion are prone to engineering disasters such as collapse, large deformation of lining, water inrush, etc., which poses a great safety hazard to the tunnel structure itself, and in severe cases, can lead to casualties and even abandonment of the tunnel project.

[0003] Fault displacement can be divided into creep and stick-slip according to the speed of time, creep is usually a slow sliding of fault with time, i.e. deformation has strong time-dependent property (rheology) and usually does not induce earthquakes or only induces small earthquakes. Stick-slip usually accompanies a large amount of elastic energy release rapidly, and transmits to the surrounding rock through seismic waves, which may cause rock burst, earthquake, existing structure cracking, even collapse accident, etc. in severe cases, and further makes the repair work difficult and the economic loss serious. From the research status at home and abroad, it can be known that at present, scholars mainly focus on the damage mechanism, support and monitoring of stick-slip faults. In actual engineering, due to the rheological property of creep fault, it is not easy to be paid attention to, but the damage degree caused by it cannot be ignored. Therefore, studying the action mechanism and deformation response characteristics of creep active fault on tunnel structure, and further improving the anti-faulting performance of long tunnel engineering crossing active fault can provide reference for its design and construction.

[0004] Due to the restriction of various factors and objective conditions, it is difficult to directly observe the damage and movement law of surrounding rock caused by fault activation. Similar material simulation test can simulate the influence of fault activation on tunnel structure and stress distribution of surrounding rock according to actual geological data on site, and artificially change test conditions, and the test results can roughly reproduce the disaster evolution process and activation law of fault. Therefore, an easy-to-operate, reliable-precision and reasonably-designed model test device is particularly important to achieve the above-mentioned goal. However, the research and development of such test devices is still concentrated in the field of stick-slip fault based on shaking table, and the device capable of realizing rheological simulation loading of creep fault tunnel is still relatively lacking. UTILITY MODEL CONTENTS

[0005] In order to study the stress and deformation of the tunnel model in the stick-slip fault field, a tunnel simulation loading test device suitable for crossing the creep fault is provided.

[0006] To this end, the utility model discloses the following technical solutions:

[0007] A tunnel simulation loading test device suitable for crossing the creep fault, comprising two parallelly laid model boxes, the left side is a fixed model box, the right side is a movable model box, and a space is left between the two model boxes; the left side, the front side, the back side and the bottom surface of the fixed model box are closed surfaces, and the right side is a hollow surface; the right side, the front side, the back side and the bottom surface of the movable model box are closed surfaces, and the left side is a hollow surface, and the hollow surfaces of the fixed model box and the movable model box face each other; a horizontal moving assembly and a vertical moving assembly are connected to the movable model box, for driving the movable model box to realize horizontal movement and vertical movement;

[0008] A stretchable connecting belt is connected between the hollow surfaces of the two model boxes, and is connected between the side surfaces and the bottom surfaces of the two model boxes, for sealing the test soil in the model boxes; the two model boxes are internally communicated, the model boxes are filled with surrounding rock and a tunnel model, the tunnel model is provided with a detection sensor, and the deformation condition of the tunnel model is monitored by the sensor when the movable model box moves.

[0009] Further, a frame is further included, which is a rigid structure, and the fixed model box and the movable model box are placed in the frame.

[0010] Further, a bearing foundation is further included, which is placed below the fixed model box, and is used for raising the fixed model box.

[0011] Further, the movable model box is connected with a vertical third jack at the bottom, the third jack is connected with a horizontal moving assembly at the bottom, the horizontal moving assembly comprises a third horizontal guide rail, a third frame body and a third roller, the third jack is fixedly connected to the third frame body, the third roller is connected to the third frame body, and the third roller can move along the third horizontal guide rail;

[0012] The top of the movable model box is connected with a vertical second jack, the second jack is connected with a second frame body at the top, the second frame body is connected with a second roller, the top of the frame is connected with a second horizontal guide rail, and the second roller can move along the second horizontal guide rail; the bottom of the second jack is fixedly connected with a horizontal pressure plate, the pressure plate is embedded into the top of the movable model box, and the pressure plate is used for applying pressure to the surrounding rock in the movable model box.

[0013] Furthermore, a vertical first jack is connected to the top of the fixed model box. The top of the first jack is fixed to the frame, and a horizontal pressure plate is connected to the bottom of the first jack. The pressure plate is embedded in the top of the fixed model box and is used to apply pressure to the surrounding rock inside the fixed model box.

[0014] Furthermore, the detection sensors include strain gauges, earth pressure gauges, and dial gauges. The strain gauges and earth pressure gauges are attached to the outer surface of the tunnel model, specifically including the invert arch, arch crown, two side arch feet, and arch foot area. The sensors are distributed at intervals along the cross sections of the tunnel model. The dial gauges are fixed to the top or bottom of the movable model box to monitor vertical displacement values.

[0015] Furthermore, it also includes an elastic support assembly, which is connected between the sides of the two model boxes and located outside the telescopic connecting strip. The elastic support assembly includes two inclined rotating rods, which are parallel and close to the sides of the model boxes. The two rotating rods are the first rotating rod and the second rotating rod, respectively. The upper end of the first rotating rod is hinged to the top of the fixed model box, and the lower end of the second rotating rod is hinged to the bottom of the movable model box. Multiple springs are connected between the first rotating rod and the second rotating rod at intervals, and the springs are arranged in parallel.

[0016] Furthermore, the lower end of the first rotating rod is hinged to a first telescopic rod, which is in close contact with the side of the model box, and the other end of the first telescopic rod is hinged to the bottom of the model box; the upper end of the second rotating rod is hinged to a second telescopic rod, which is in close contact with the side of the model box, and the other end of the second telescopic rod is hinged to the top of the movable model box.

[0017] The beneficial effects of this utility model are as follows:

[0018] 1. This utility model can simulate loading across a creep fault tunnel and intuitively reproduce the influence of the rheological properties of the creep fault on the tunnel structure;

[0019] 2. By setting a second jack on the top of the movable model box, the second jack applies pressure to the surrounding rock inside the movable model box, thereby achieving vertical stress compensation for the deep-buried tunnel and more realistically reversing the original rock stress state of the deep-buried tunnel.

[0020] 3. By setting springs and telescopic connecting belts, the contraction and shear deformation between the two model boxes can be realized. Compared with the previous model boxes that could only realize shear displacement, it can more accurately reflect the stress and deformation of the creep fault.

[0021] 4. The side walls of the two model boxes can be made of plexiglass, which makes it easy for the test personnel to observe and record the deformation and failure of the surrounding rock at any time;

[0022] 5. This utility model device can be connected to a deformation and stress monitoring system, which can realize continuous deformation and stress state monitoring of tunnel structure and surrounding rock under fault creep, providing a reliable device and method for the study of large deformation mechanism of tunnel structure;

[0023] 6. The device of this utility model is simple in principle and easy to operate, meets the test requirements under different fault parameter conditions, is easy to reuse, and has good versatility. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the experimental device of this utility model;

[0025] Figure 2 This is a schematic diagram of the structure of the fixed model box of the experimental device of this utility model;

[0026] Figure 3 This is a schematic diagram of the structure of the movable model box of the experimental device of this utility model;

[0027] Figure 4 This is a structural schematic diagram of the telescopic connecting belt and elastic support assembly of this utility model;

[0028] Figure 5 This is a structural schematic diagram of the elastic support component of this utility model;

[0029] Figure 6 This is a structural schematic diagram of the telescopic connecting belt of this utility model;

[0030] In the diagram: Fixed model box 1, movable model box 2, frame 3, bearing foundation 4, first jack 5, second jack 6, third jack 7, second roller 8, second horizontal guide rail 9, third roller 10, third horizontal guide rail 11, first rotating rod 12, column 13, hinge shaft 14, first telescopic rod 16, spring 17, telescopic connecting belt 18. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0032] like Figure 1As shown, a simulation loading test device for tunnels across creep faults includes a frame 3, which is a rigid cubic frame structure. It includes two parallel model boxes: a fixed model box 1 on the left and a movable model box 2 on the right. The fixed model box 1 and the movable model box 2 are placed within the frame 3, with a gap between them. The left, front, rear, and bottom surfaces of the fixed model box 1 are closed, while the right side is open. The right, front, rear, and bottom surfaces of the movable model box 2 are closed, while the left side is open. The open surfaces of the fixed model box 1 and the movable model box 2 face each other. A horizontal movement component and a vertical movement component are connected to the movable model box 2 to drive it to move horizontally and vertically.

[0033] like Figure 1 and 4 As shown, a telescopic connecting strap 18 is connected between the hollow surfaces of the two model boxes. The telescopic connecting strap 18 is connected between the sides and bottom surfaces of the two model boxes. The telescopic connecting strap 18 is used to seal the test soil inside the model box. The telescopic connecting strap 18 is made of elastic rubber sheet material.

[0034] The two model boxes are internally connected, and each model box contains surrounding rock and a tunnel model. Detection sensors are installed on the tunnel model, and the deformation of the tunnel model is monitored by the sensors when the movable model box 2 moves. A supporting foundation 4 is also included, which is placed below the fixed model box 1 and is used to elevate the fixed model box 1.

[0035] like Figure 2 and 3 As shown, the bottom of the movable model box 2 is connected to a vertical third jack 7. The bottom of the third jack 7 is connected to a horizontal moving assembly, which includes a third horizontal guide rail 11, a third frame, and third rollers 10. The third jack 7 is fixedly connected to the third frame, and the third rollers 10 are also connected to the third frame and can move along the third horizontal guide rail 11. The top of the movable model box 2 is connected to a vertical second jack 6. The top of the second jack 6 is connected to a second frame, and second rollers 8 are connected to the second frame. The top of the frame 3 is connected to a second horizontal guide rail 9, and the second rollers 8 can move along the second horizontal guide rail 9. To ensure the stable movement of the movable model box 2, a support guide rod (not shown in the figure) is also connected between the third frame and the bottom of the movable model box 2. The support guide rod is located at the four corners to ensure the stability of the movable model box 2. A horizontal pressure plate is fixedly connected to the bottom of the second jack 6. The pressure plate is embedded in the top of the movable model box 2 and is used to apply pressure to the surrounding rock inside the movable model box 2.

[0036] like Figure 2As shown, a vertical first jack 5 is connected to the top of the fixed model box 1. The top of the first jack 5 is fixed to the frame 3. A horizontal pressure plate is connected to the bottom of the first jack 5. The pressure plate is embedded in the top of the fixed model box 1 and is used to apply pressure to the surrounding rock inside the fixed model box 1.

[0037] The detection sensors include strain gauges, earth pressure gauges, and dial gauges. The strain gauges and earth pressure gauges are attached to the outer surface of the tunnel model, specifically including the invert arch, arch crown, two side arch feet, and arch foot area. The sensors are distributed at intervals along the cross sections of the tunnel model. The dial gauges are fixed to the top or bottom of the movable model box 2 to monitor vertical displacement values.

[0038] like Figure 4 and 5 As shown, it also includes an elastic support assembly, which is connected between the sides of the two model boxes and located outside the telescopic connecting strip 18. The elastic support assembly includes two inclined rotating rods, which are parallel and close to the sides of the model boxes. The two rotating rods are a first rotating rod 12 and a second rotating rod, respectively. The upper end of the first rotating rod 12 is hinged to the top of the fixed model box 1, and the lower end of the second rotating rod is hinged to the bottom of the movable model box 2. A plurality of springs 17 are connected between the first rotating rod 12 and the second rotating rod at intervals, and the springs 17 are arranged in parallel. The lower end of the first rotating rod 12 is hinged to a first telescopic rod 16, which is close to the side of the model box. The other end of the first telescopic rod 16 is hinged to the bottom of the fixed model box 1. The upper end of the second rotating rod is hinged to a second telescopic rod, which is close to the side of the model box. The other end of the second telescopic rod is hinged to the top of the movable model box 2.

Claims

1. A simulation loading test device suitable for tunnels crossing creep faults, characterized in that, It includes two model boxes arranged side by side, with a fixed model box (1) on the left and a movable model box (2) on the right, with a gap between the two model boxes; the left, front, back and bottom surfaces of the fixed model box (1) are closed, and the right side is open; the right, front, back and bottom surfaces of the movable model box (2) are closed, and the left side is open, with the open surfaces of the fixed model box (1) and the movable model box (2) facing each other; the movable model box (2) is connected to a horizontal moving component and a vertical moving component, which are used to drive the movable model box (2) to achieve horizontal and vertical movement; A telescopic connecting strip (18) is connected between the hollow surfaces of the two model boxes. The telescopic connecting strip (18) is connected between the sides and bottom of the two model boxes. The telescopic connecting strip (18) is used to seal the test soil inside the model box. The two model boxes are connected internally. The model boxes are filled with surrounding rock and tunnel models. Detection sensors are installed on the tunnel model. When the movable model box (2) moves, the deformation of the tunnel model is monitored by the sensors.

2. The simulated loading test device for tunnels across creep faults according to claim 1, characterized in that, It also includes a frame (3), which is a rigid structure, with the fixed model box (1) and the movable model box (2) placed inside the frame (3).

3. The simulated loading test device for tunnels across creep faults according to claim 2, characterized in that, It also includes a support base (4), which is placed under the fixed model box (1) and is used to raise the fixed model box (1).

4. The simulated loading test device for tunnels across creep faults according to claim 2, characterized in that, The bottom of the movable model box (2) is connected to a vertical third jack (7), and the bottom of the third jack (7) is connected to a horizontal moving component. The horizontal moving component includes a third horizontal guide rail (11), a third frame and a third roller (10). The third jack (7) is fixedly connected to the third frame, and the third roller (10) is connected to the third frame. The third roller (10) can move along the third horizontal guide rail (11). The top of the movable model box (2) is connected to a vertical second jack (6), the top of the second jack (6) is connected to a second frame, the second frame is connected to a second roller (8), the top of the frame (3) is connected to a second horizontal guide rail (9), the second roller (8) can move along the second horizontal guide rail (9); the bottom of the second jack (6) is fixedly connected to a horizontal pressure plate, the pressure plate is embedded in the top of the movable model box (2), and the pressure plate is used to apply pressure to the surrounding rock inside the movable model box (2).

5. The simulated loading test device for tunnels across creep faults according to claim 4, characterized in that, The top of the fixed model box (1) is connected to a vertical first jack (5), the top of the first jack (5) is fixed to the frame (3), and the bottom of the first jack (5) is connected to a horizontal pressure plate. The pressure plate is embedded in the top of the fixed model box (1) and is used to apply pressure to the surrounding rock inside the fixed model box (1).

6. The simulated loading test device for tunnels across creep faults according to claim 1, characterized in that, The detection sensors include strain gauges, earth pressure gauges and dial gauges. The strain gauges and earth pressure gauges are attached to the outer surface of the tunnel model, specifically including the inverted arch, the arch top, the two sides of the arch foot and the arch foot. The sensors are distributed at intervals on the tunnel model. The dial gauge is fixed to the top or bottom of the movable model box (2) to monitor the vertical displacement value.

7. The simulated loading test device for tunnels across creep faults according to claim 1, characterized in that, It also includes an elastic support assembly, which is connected between the sides of the two model boxes and located outside the telescopic connecting strip (18). The elastic support assembly includes two inclined rotating rods, which are parallel and close to the sides of the model box. The two rotating rods are the first rotating rod (12) and the second rotating rod, respectively. The upper end of the first rotating rod (12) is hinged to the top of the fixed model box (1), and the lower end of the second rotating rod is hinged to the bottom of the movable model box (2). Multiple springs (17) are connected between the first rotating rod (12) and the second rotating rod at intervals, and each spring (17) is arranged in parallel.

8. The simulated loading test device for tunnels across creep faults according to claim 7, characterized in that, The lower end of the first rotating rod (12) is hinged to a first telescopic rod (16), which is close to the side of the model box. The other end of the first telescopic rod (16) is hinged to the bottom of the fixed model box (1). The upper end of the second rotating rod is hinged to a second telescopic rod, which is close to the side of the model box. The other end of the second telescopic rod is hinged to the top of the movable model box (2).

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