A rock structure surface shear creep device capable of dry-wet cycle

Abstract

The present invention discloses a rock structural surface shear creep device capable of dry-wet cycles, comprising an upper shear box, a lower shear box, a guide column and a translation mechanism, wherein the upper and lower shear boxes are both open and arranged opposite to each other to form a cavity for accommodating rocks, wherein the total height of the rocks is greater than the total height of the cavities in the upper and lower shear boxes, and the structural surface is located in the gap interval of the upper and lower shear boxes; at least two dry-wet cycle holes are arranged on the upper shear box, and the dry-wet cycle holes are located at the periphery of the cavity for accommodating rocks, and the outer walls of the upper and lower shear boxes have the same size and are sealed and connected to form a circulation channel that can be connected through the structural surface of the rock; the upper shear box and the lower shear box are both penetrated on the guide column, and the guide column is arranged on the base of the translation mechanism, and the lower shear box is arranged on the sliding plate of the translation mechanism. The device of the present invention is low in cost, simple and practical, and can realize shear experiments on rock structural surfaces under saturated or unsaturated conditions, and realize shear creep experimental operations on rock structural surfaces after dry-wet cycles.

Description

Technical Field

[0001] The invention relates to the technical field of rock structure surface shear creep, in particular to a rock structure surface shear creep device capable of dry-wet cycle. Background Art

[0002] During the long-term operation of reservoir water storage, the periodic fluctuation of reservoir water level causes the reservoir bank slope to be in a long-term saturated and unsaturated dry-wet cycle process. Long-term dry-wet cycles will cause the physical properties of the rock structural surface of the reservoir bank slope to deteriorate, and eventually lead to the stability of the reservoir bank slope, seriously affecting the safety of the reservoir. At present, most reservoirs have been in operation for a long time, and there is a general risk of slope instability under long-term water level fluctuation conditions. Among the reservoir instability cases that have occurred, most are related to the instability and destruction of the slope structural surface and weak surface. Therefore, the study of the shear creep characteristics of the rock structural surface under the action of dry-wet cycles is very necessary for the stability evaluation of the reservoir bank slope.

[0003] Under the action of dry-wet cycles, the physical properties of the rock mass structural surface will deteriorate, with varying degrees of deterioration in mechanical strength, cohesion and internal friction angle. The creep deformation of the structural surface caused by long-term dry-wet action is an important reason for the reduction of slope stability, which ultimately leads to slope instability.

[0004] At present, the traditional method of shear creep of rock structural surface is to put the upper and lower rock specimens into a container and soak them. After the experiment, the structural surface materials are taken out and dried, and finally the shear creep experiment is carried out. Such repeated dry-wet cycle operation divides the shear creep experiment into two independent steps. The operation process is cumbersome and too much manual operation on the specimens can easily damage the rock material and cause rock damage, resulting in a large error between the experimental results and the actual situation. This also has another defect, that is, it is impossible to carry out shear test on the structural surface under saturation. Summary of the invention

[0005] The purpose of the present invention is to provide a rock structure surface shear creep device capable of dry-wet cycle to solve the problems existing in the above-mentioned prior art, so that the dry-wet cycle operation in the rock structure surface shear creep experimental device is convenient to operate, the number of dry-wet cycles can be controlled, and the shear creep experiment on the rock structure surface under saturated or unsaturated state can be realized.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a rock structural surface shear creep device capable of dry-wet cycle, comprising an upper shear box, a lower shear box, a guide column and a translation mechanism, wherein the upper shear box and the lower shear box are both open and arranged opposite to each other, forming a cavity for accommodating two oppositely arranged rocks, wherein the total height of the two rocks is greater than the total height of the cavities in the upper shear box and the lower shear box, and the structural surface of the rock is located in the gap between the upper shear box and the lower shear box; at least two dry-wet cycle holes are arranged on the upper shear box, and the dry-wet cycle holes are located on the periphery of the cavity accommodating the rock, and the The dry-wet circulation hole is used to connect a water source or dry hot air. The outer walls of the upper shear box and the lower shear box have the same size and are sealed and connected to form a circulation channel for water or gas. The circulation channel can be connected through the structural surface of the rock. The upper shear box and the lower shear box are both passed through the guide column, and the guide column is arranged on the base of the translation mechanism. The lower shear box is arranged on the sliding plate of the translation mechanism. The sliding plate and the base can slide relative to each other. The top of the upper shear box can be used to apply normal pressure, and the side wall of the lower shear box can be used to apply lateral shear force.

[0008] Preferably, the upper shear box and the lower shear box are respectively provided with locking mechanisms for adjusting rock displacement, and the locking mechanisms include a baffle and a bolt. The baffle is arranged in the cavity of the upper shear box or the lower shear box, and the bolt passes through the cavity wall of the upper shear box or the lower shear box and is connected to the baffle, so that the structural surfaces of the two rocks are aligned.

[0009] Preferably, the height of the baffles is smaller than the height of the corresponding rocks, and the baffles are respectively located on opposite surfaces of the cavity.

[0010] Preferably, the dry-wet circulation holes include air inlet holes, air outlet holes, water inlet holes and water outlet holes evenly distributed on the top of the upper shear box, the air inlet holes and the air outlet holes, the water inlet holes and the water outlet holes are respectively located on opposite surfaces of the upper shear box, and the air outlet holes are connected to the vacuum pump through a pipeline.

[0011] Preferably, a humidity sensor is provided in the air outlet or on a pipeline connected to the air outlet, and valves are provided on the air inlet, the water inlet, the air outlet and the pipeline connected to the water outlet.

[0012] Preferably, a drainage hole is provided on the lower shear box, one end of the drainage hole is connected to the circulation channel, and the other end of the drainage hole is connected to a water collecting tank through a pipeline, and the pipeline is provided with a valve.

[0013] Preferably, the translation mechanism includes a base, rollers and a sliding plate, the base is in a "concave" shape, a plurality of rollers are arranged in the base parallel to the side walls of the base, the sliding plate is arranged on the rollers, and the length of the sliding plate is smaller than the distance between the two side walls of the base.

[0014] Preferably, a mounting limit bolt is provided on the side wall of the base, and the mounting limit bolt can be pressed against the side wall of the lower shear box.

[0015] Preferably, a displacement sensor is provided on the side wall of the base, and the displacement sensor is located on one side of the installation limit bolt.

[0016] Preferably, the top of the upper shear box and the side of the lower shear box are respectively provided with a frustum for applying force, and the outer walls of the upper shear box and the lower shear box are sealed by a circle of baffle plates, one side of which is detachable.

[0017] Compared with the prior art, the present invention has achieved the following technical effects:

[0018] The present invention can provide a closed environment for dry-wet cycles for rock structural surfaces, more conveniently perform dry-wet cycle operations, greatly reduce the influence of human factors in the dry-wet cycle process, simulate actual dry-wet cycle conditions, and improve experimental accuracy; saturated water is introduced into the shear box cavity to simulate automatic water level rise, and the water level drop is achieved by using drainage holes, which is more in line with the actual water level fluctuation in the slope drawdown zone of the reservoir, and the structure is simple and easy to operate; the device is low in cost, simple and practical, can realize shear experiments on rock structural surfaces under saturated or unsaturated states, and realize shear creep experimental operations on the shear structural surface after dry-wet cycle action. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 The structure of the rock structure surface shear creep device capable of dry-wet cycles of the present invention is shown in FIG. Figure 1 ;

[0021] Figure 2 The structure of the rock structure surface shear creep device capable of dry-wet cycles of the present invention is shown in FIG. Figure 2 ;

[0022] Figure 3 This is an internal structural diagram of the rock structure surface shear creep device capable of dry-wet cycles of the present invention;

[0023] Among them: 1-upper shear box, 2-lower shear box, 3-guide column, 4-truncated table, 5-enclosing plate, 6-rock, 7-structural surface, 8-baffle, 9-bolt, 10-circulation channel, 11-air inlet, 12-air outlet, 13-water inlet, 14-water outlet, 15-drainage hole, 16-base, 17-roller, 18-sliding plate, 19-installation limit bolt, 20-displacement sensor. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The purpose of the present invention is to provide a rock structure surface shear creep device capable of dry-wet cycle to solve the problems existing in the prior art, so that the dry-wet cycle operation in the rock structure surface shear creep experimental device is convenient to operate, the number of dry-wet cycles can be controlled, and the shear creep experiment on the rock structure surface under saturated or unsaturated state can be realized.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] like Figures 1 to 3As shown: This embodiment provides a rock structural surface shear creep device capable of dry-wet cycle, comprising an upper shear box 1, a lower shear box 2, a guide column 3 and a translation mechanism, the upper shear box 1 and the lower shear box 2 are both open and the openings are arranged opposite to each other, forming a cavity for accommodating two relatively arranged rocks 6, the total height of the two rocks 6 is greater than the total height of the inner cavity of the upper shear box 1 and the lower shear box 2, the structural surface 7 of the rock 6 is located in the gap between the upper shear box 1 and the lower shear box 2; at least two dry-wet cycle holes are arranged on the upper shear box 1, and the dry-wet cycle holes are located around the cavity accommodating the rock 6 The dry-wet circulation hole is used to connect the water source or dry hot air. The outer walls of the upper shear box 1 and the lower shear box 2 have the same size and are sealed to form a circulation channel 10 for water or gas. The circulation channel 10 can be connected through the structural surface 7 of the rock 6; the upper shear box 1 and the lower shear box 2 are both penetrated on the guide column 3, and the guide column 3 is arranged on the base 16 of the translation mechanism. The lower shear box 2 is arranged on the sliding plate 18 of the translation mechanism. The sliding plate 18 and the base 16 can slide relative to each other. The top of the upper shear box 1 can be used to apply normal pressure, and the side wall of the lower shear box 2 can be used to apply lateral shear force. The top of the upper shear box 1 and the side of the lower shear box 2 are respectively provided with a truncated cone 4 for applying force. The outer walls of the upper shear box 1 and the lower shear box 2 are sealed by a circle of baffle plates 5. One side of the baffle plates 5 is detachable to facilitate the disassembly and assembly of the baffle plates 5.

[0028] The upper shear box 1 and the lower shear box 2 are respectively provided with locking mechanisms for adjusting the displacement of the rock 6. The locking mechanisms include baffles 8 and bolts 9. The baffles 8 are arranged in the cavity of the upper shear box 1 or the lower shear box 2. The bolts 9 pass through the cavity wall of the upper shear box 1 or the lower shear box 2 and are connected or in conflict with the baffles 8, so that the structural surfaces 7 of the two rocks 6 are aligned. The height of the baffles 8 is less than the height of the corresponding rock 6 (lower than the end face of the cavity in this embodiment), and the baffles 8 are respectively located on the opposite faces of the cavity. Since there is a small error in the volume of the rock 6 (specimen) used in the experiment, the lateral adjustment of the locking mechanism facilitates the alignment of the structural surface 7 of the rock 6 and reduces the experimental error.

[0029] The dry-wet circulation holes include an air inlet 11, an air outlet 12, a water inlet 13 and a water outlet 14 uniformly distributed on the top of the upper shear box 1. The air inlet 11 and the air outlet 12, the water inlet 13 and the water outlet 14 are respectively located on the opposite surfaces of the upper shear box 1, and the air outlet 12 is connected to the vacuum pump through a pipeline. A humidity sensor is arranged in the air outlet 12 or on the pipeline connected to the air outlet 12, which can record the humidity changes in the cavity of the rock 6, so as to facilitate the grasp of the time of the dry-wet cycle. Valves are arranged on the pipelines connected to the air inlet 11, the air outlet 12, the water inlet 13 and the water outlet 14, so as to ensure the airtightness of the circulation channel 10. A drainage hole 15 is arranged on the lower shear box 1, one end of the drainage hole 15 is connected to the circulation channel 10, and the other end of the drainage hole 15 is connected to a water collecting tank through a pipeline, and the pipeline is provided with a valve. Compared with the traditional dry-wet cycle operation method, the setting of the dry-wet cycle hole has a simple structure and is more convenient for dry-wet cycle operation, greatly reducing the influence of human factors in the dry-wet cycle process, more closely fitting the simulation of actual dry-wet cycle conditions, and improving experimental accuracy.

[0030] The translation mechanism includes a base 16, a roller 17 and a sliding plate 18. The base 16 is in a "concave" shape to facilitate limiting the movement of the roller 17. A plurality of rollers 17 are arranged in the base 16 parallel to the side wall of the base 16. A sliding plate 18 is arranged on the roller 17. The length of the sliding plate 18 is less than the distance between the two side walls of the base 16, so that when the lateral shear force is applied, the sliding plate 18 and the lower shear box 2 can slide in the base 16. A mounting limit bolt 19 is arranged on the side wall of the base 16, and the mounting limit bolt 19 can be against the side wall of the lower shear box 2. A displacement sensor 20 is arranged on the side wall of the base 16, and the displacement sensor 20 is located on one side of the mounting limit bolt 19. Preferably, the displacement sensor 20 is electrically connected to a temperature sensor and a control device to facilitate the output of experimental data.

[0031] The specific steps of using the rock structure surface shear creep device capable of dry-wet cycles of this embodiment are as follows: first install the device, place it stably, and connect the shear creep instrument. Before the experiment, prestress can be applied according to the actual engineering situation to simulate the actual engineering pressure situation.

[0032] Wet-dry cycle operation process: close the valves on the water outlet 14, drainage hole 15, and water inlet 13 pipelines, open the valves on the air inlet 11 and air outlet 12 pipelines, and blow hot air into the rock cavity of the upper and lower shear boxes until the structural surface 7 of the rock 6 is completely dry. Close the valve on the air inlet 11 pipeline, open the vacuum pump to pump air and the valve on the water inlet 13 pipeline, and pump water into the rock cavity of the upper and lower shear boxes until the structural surface 7 of the rock 6 is completely saturated. After the saturation process of the structural surface 7 is completed, open the valve on the drainage hole 15 pipeline of the lower shear box 2 to discharge the water stored in the middle rock cavity, and repeat the above operation to complete multiple wet-dry cycles.

[0033] Shear creep operation process: remove the installation limit bolt 19, release the displacement limit of the lower shear box 2, apply normal pressure to the truncated cone 4 on the top of the upper shear box, wait for the normal displacement to stabilize, apply lateral shear force to the truncated cone 4 on the side of the lower shear box 2, so that the lower shear box 2 produces relative displacement on the base 16, and the shear stress is recorded by the stress sensor of the shear creep instrument, and the displacement sensor 20 records the shear creep displacement. Among them, the normal load applied by the shear creep instrument plus the deadweight of the upper shear box 1 is the total normal load on the structural surface 7, and the normal stress can be obtained by dividing the total normal load by the shear area of ​​the rock structural surface. After completing the first-level shear load test, after the shear creep displacement reaches stability, the next-level shear load loading experiment can be carried out until the rock structural surface sample is shear creep destroyed. After the experiment is completed, according to the conventional creep experiment process, the experimental data needs to be analyzed and processed, and the relationship between creep displacement-time and the relationship between normal stress and creep characteristics can be obtained.

[0034] The present specification uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A rock structure surface shear creep device capable of dry-wet cycles, characterized in that: It comprises an upper shear box, a lower shear box, a guide column and a translation mechanism, the upper shear box and the lower shear box are both open and arranged opposite to each other, forming a cavity for accommodating two oppositely arranged rocks, the total height of the two rocks is greater than the total height of the inner cavities of the upper shear box and the lower shear box, the structural surface of the rock is located in the gap between the upper shear box and the lower shear box; at least two dry-wet circulation holes are provided on the upper shear box, the dry-wet circulation holes are located on the periphery of the cavity accommodating the rock, the dry-wet circulation holes are used to connect a water source or dry hot air, the outer walls of the upper shear box and the lower shear box have the same size and are sealed and connected, forming a circulation channel for water or gas, and the circulation channel can be connected through the structural surface of the rock; the upper shear box and the lower shear box are both passed through the guide column, the guide column is arranged on the base of the translation mechanism, and the lower The shear box is arranged on the sliding plate of the translation mechanism, and the sliding plate and the base can slide relative to each other. The top of the upper shear box can be used to apply normal pressure, and the side wall of the lower shear box can be used to apply lateral shear force; the upper shear box and the lower shear box are respectively provided with locking mechanisms for adjusting rock displacement, and the locking mechanism includes a baffle and a bolt, and the baffle is arranged in the cavity of the upper shear box or the lower shear box, and the bolt passes through the cavity wall of the upper shear box or the lower shear box and is connected to the baffle, so that the structural surfaces of the two rocks are aligned; the height of the baffle is less than the height of the corresponding rock, and the baffles are respectively located on the opposite surfaces of the cavity, and the lower shear box is provided with a drainage hole, one end of the drainage hole is connected to the circulation channel, and the other end of the drainage hole is connected to a water collecting tank through a pipeline, and the pipeline is provided with a valve.

2. The rock structure surface shear creep device capable of dry-wet cycles according to claim 1 is characterized in that: The dry-wet circulation holes include air inlet holes, air outlet holes, water inlet holes and water outlet holes evenly distributed on the top of the upper shear box. The air inlet holes and the air outlet holes, the water inlet holes and the water outlet holes are respectively located on opposite surfaces of the upper shear box, and the air outlet holes are connected to the vacuum pump through a pipeline.

3. The rock structure surface shear creep device capable of dry-wet cycles according to claim 2 is characterized in that: A humidity sensor is arranged in the air outlet or on a pipeline connected to the air outlet, and valves are arranged on the air inlet, the water inlet, the air outlet and a pipeline connected to the water outlet.

4. The rock structure surface shear creep device capable of dry-wet cycles according to claim 1, characterized in that: The translation mechanism includes a base, a roller and a sliding plate. The base is in a "concave" shape. A plurality of rollers are arranged in the base parallel to the side walls of the base. The sliding plate is arranged on the roller. The length of the sliding plate is less than the distance between the two side walls of the base.

5. The rock structure surface shear creep device capable of dry-wet cycles according to claim 4 is characterized in that: A mounting limit bolt is arranged on the side wall of the base, and the mounting limit bolt can abut against the side wall of the lower shear box.

6. The rock structure surface shear creep device capable of dry-wet cycles according to claim 5, characterized in that: A displacement sensor is arranged on the side wall of the base, and the displacement sensor is located on one side of the installation limit bolt.

7. The rock structure surface shear creep device capable of dry-wet cycles according to claim 1, characterized in that: The top of the upper shear box and the side of the lower shear box are respectively provided with a truncated table for applying force, and the outer walls of the upper shear box and the lower shear box are sealed by a circle of baffle plates, one side of which is detachable.

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