Simulation test method and device for strike-slip fault generating oblique fracture

Abstract

The invention provides a simulation test method and device for a strike-slip fault generating oblique fracture, and relates to the technical field of seismic fault simulation, and the device comprises a test bed, two model boxes, a flexible enclosure assembly and a driving assembly; connecting openings are formed in the end parts of the two model boxes, and the connecting openings of the two model boxes are oppositely arranged; the flexible enclosure assembly is flexibly connected with a connecting opening of the two model boxes, the simulation area is filled with a test soil body, a test model is arranged on the test soil body, and a pressure sensor and a displacement sensor are attached to the test model; the two model boxes are respectively a fixed model box and a dislocation model box, and the driving module is used for driving the driving sliding table to slide on the test bed, so that a test soil body in the fixed model box and a test soil body in the fixed model box are subjected to dislocation movement. According to the test device and method provided by the invention, the problem of equipment limitation in current research can be overcome, the research depth and breadth in the seismic fault field are expanded, and the test device and method have good theoretical significance and practical application value.

Description

Technical Field

[0001] The present invention relates to the technical field of earthquake fault simulation, and specifically to a strike-slip fault simulation test method and device for generating oblique fractures. Background Art

[0002] With the continuous transfer of China's economic construction to the southwest and the successive launch of a series of important engineering projects, the demand for relevant scientific research has been increasing day by day. The southwest region is located at the southeastern edge of the Qinghai-Tibet Plateau and at the intersection of the Indian plate and the Eurasian plate. The crustal movement is active and the geological structure is complex, making it difficult for major projects to avoid active fault zones, posing a huge challenge to engineering construction.

[0003] With the progress of technology, the scaled model test can effectively control the test conditions and process, reproduce the fault dislocation phenomenon, and provide important support for the research on cross-fault engineering. At present, in the cross-fault model test, hydraulic pumps, cylinders and other driving devices are often used to load the model box at a fixed angle to simulate the fault dislocation phenomenon. The load input method of this fault simulation method is complex, it is difficult to accurately reflect the displacement distribution inside the fault fracture zone, and the development process of soil cracks cannot be directly observed during the test. Moreover, most devices can only simulate the fault activity phenomenon under specific working conditions (such as fixed fault width and included angle), and the cost of special devices for prefabricating multiple working conditions is high and the maintenance is difficult. Therefore, there is an urgent need for a general fault simulation method to generate continuous oblique cracks with a controllable included angle in the test soil body, so as to more effectively study the influence of strike-slip fault dislocation on underground civil engineering structures. Summary of the Invention

[0004] In view of this, the present invention provides a strike-slip fault simulation test device for generating oblique fractures, including a test bench, two model boxes, a flexible enclosure assembly and a driving assembly;

[0005] Connection openings are provided at both ends of the two model boxes, and the connection openings of the two model boxes are arranged opposite to each other;

[0006] The flexible enclosure assembly flexibly connects the connection openings of the two model boxes, thereby connecting the inner spaces at both ends of the two model boxes to form a simulation area. The simulation area is filled with test soil, and a test model for simulating an engineering structure is arranged on the test soil. The test model is partially or completely buried in the test soil, and data collection devices such as pressure sensors and displacement sensors are attached to the test model;

[0007] The two model boxes are a fixed model box and a misaligned model box respectively. The fixed model box is fixedly arranged on the test bench. The driving assembly includes a driving slide and a plurality of driving modules with different driving directions. The misaligned model box is fixed on the driving slide. The driving module is used to drive the driving slide to slide on the test bench, so that the test soil in the fixed model box and the test soil in the misaligned model box undergo misaligned movement.

[0008] Further, the flexible enclosure assembly includes geotextile and two transparent soft curtains. Both ends of the geotextile and the two transparent soft curtains are connected between the connection openings of the fixed model box and the misaligned model box. The connection openings of the fixed model box and the misaligned model box are arranged at intervals with a misalignment gap. The geotextile is at the bottom of the misalignment gap, and the two transparent soft curtains are located on both sides of the misalignment gap.

[0009] Further, the model box includes a fixed frame and transparent plates filled on the sides of the fixed frame.

[0010] Further, a monitoring camera is also included. The monitoring camera faces the two model boxes and is used to capture test images.

[0011] Further, the driving module includes a transverse moving cylinder and a longitudinal moving cylinder. Both ends of the transverse moving cylinder and the longitudinal moving cylinder are respectively rotatably connected to the test bench and the side surface of the driving slide. The transverse moving cylinder and the longitudinal moving cylinder are vertically arranged.

[0012] Further, a driving control device is also included. The driving control device is connected to the transverse moving cylinder and the longitudinal moving cylinder at the same time. The driving control device is used to control the telescopic speed of the transverse moving cylinder and the longitudinal moving cylinder, so as to control the moving speed and direction of the driving slide.

[0013] The present invention also includes a strike-slip fault simulation test method for generating oblique fractures. This method uses the above-mentioned strike-slip fault simulation test device for generating oblique fractures. This method includes the following steps:

[0014] S1: Make a test model according to the test requirements and prepare the test soil.

[0015] S2: Debug the test device, evenly lay the prepared test soil in the simulation area, attach sensors to the test model, and install the test model inside or above the test soil according to the test design.

[0016] S3: Set up the monitoring camera to record the test process.

[0017] S4: Control the driving module to drive the sliding table to slide on the test bench, causing the moving model box to move relative to the fixed model box along a predetermined trajectory, so that the test soil mass in the simulation area is displaced, until a through crack with a predetermined displacement angle is formed in the test soil mass.

[0018] S5: Record the test images and the test data collected by the sensors.

[0019] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0020] 1. The test device has multiple driving modules with different driving directions. The driving modules work in coordination with the model box to ensure the precise control of the driving system. Compared with the existing strike-slip fault simulation methods, this method simplifies the operation process. Each driving module can apply precise displacements independently in different directions, so as to more accurately simulate the fault displacement behavior under actual geological conditions.

[0021] 2. The test device and method can simulate the behavior of strike-slip faults with different included angles without modifying the existing device, and has wide applicability and can meet different research needs.

[0022] 3. The test device and method introduce a transparent protective glass and a PVC transparent soft curtain, which can directly observe the whole process of the development of soil cracks in the fracture zone, reducing the errors caused by indirect measurement. In addition, the test parameters can be adjusted in real time dynamically to precisely control the test process, which can enhance the understanding and prediction ability of fault behavior and improve the accuracy and reliability of the test.

[0023] 4. At present, in the fault simulation test, when the model crosses the strike-slip fault with an inclined strike, the width and the inclined placement angle of the box body are limited by the size of the test platform, resulting in a significant impact of the box body boundary effect on the test results. Further, the size of the box body limits the inclined placement angle of the model, making the effective simulation area of the fault displacement smaller and restricting the flexibility of the test settings. Moreover, in most displacement fault simulation systems, the two boxes are placed closely, ignoring the influence of the fracture zone width on the test and unable to fully reflect the complexity of fault activities. The test device and method overcome these limitations by applying the flexible enclosure component. The inside of the flexible enclosure component serves as the displacement space of the test soil mass, expanding the effective simulation area of the fault activity and providing a larger displacement space. Considering the influence of the fault fracture zone width on the structure, it minimizes the influence of the box body's own structure on the form of the fracture zone to the greatest extent, enabling the soil mass to produce corresponding deformations under the relative displacement of the box bodies, so as to simulate more realistic earthquake fault activities.

[0024] The above beneficial effects can effectively make up for the problems of equipment limitations in current research, expand the research depth and breadth in the field of seismic faults, and have good theoretical significance and practical application value. Brief Description of the Drawings

[0025] Figure 1 It is a top view of a strike-slip fault simulation test device for generating oblique fractures according to an embodiment of the present invention.

[0026] Figure 2 It is a sectional view of a displacement model box and a fixed model box of a strike-slip fault simulation test device for generating oblique fractures according to an embodiment of the present invention.

[0027] Figure 3 It is a schematic diagram of a dislocation gap structure of a strike-slip fault simulation test device for generating oblique fractures according to an embodiment of the present invention.

[0028] In the above figures: 1 - test bench, 11 - fixed plate, 12 - fixed seat, 2 - driving slide, 3 - transverse moving cylinder, 31 - longitudinal moving cylinder, 4 - fixed model box, 5 - displacement model box, 6 - geotextile, 61 - transparent soft curtain, 7 - test model, 71 - support beam, 72 - fixed pile, 73 - displacement gap, 8 - monitoring camera. Detailed Embodiment

[0029] To make the objectives, technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

[0030] Please refer to Figures 1 to 3 , a strike-slip fault simulation test device for generating oblique fractures of the present invention includes a test bench 1, two model boxes, a flexible enclosure assembly and a driving assembly. A fixed plate 11 and a fixed seat 12 are fixedly arranged on the test bench.

[0031] Both of the two model boxes are rectangular boxes with open tops, and connection openings are provided at the ends of both model boxes, and the connection openings of the two model boxes are arranged oppositely; the flexible enclosure assembly flexibly connects the connection openings of the two model boxes, so as to connect the inner spaces at the ends of the two model boxes to form a simulation area. The simulation area is filled with test soil, and a test model 7 for simulating an engineering structure is arranged on the test soil, and the test model 7 is partially or completely buried in the test soil, and pressure sensors and displacement sensors are attached to the test model 7.

[0032] The two model boxes are respectively a fixed model box 4 and a misaligned moving model box 5. The fixed model box 4 is fixedly arranged on the fixed seat 12 of the test bench 1. The driving assembly includes a driving slide 2 and multiple driving modules with different driving directions. The misaligned model box 5 is fixed on the driving slide 2. The height of the fixed seat 12 is the same as that of the driving slide 2, so that the bottoms of the two model boxes are at the same height.

[0033] The driving module is used to drive the driving slide 2 to slide on the test bench 1, so that the test soil body in the fixed model box 5 and the test soil body in the fixed model box 5 undergo misaligned movement.

[0034] In a preferred embodiment, the flexible enclosure assembly includes a geotextile 6 and two transparent soft curtains 61. Both ends of the geotextile 6 and the two transparent soft curtains 61 are connected between the connection opening of the fixed model box 5 and the misaligned model box. The connection opening of the fixed model box 5 and the misaligned model box 5 are arranged at intervals with a misalignment gap. The geotextile 6 is at the bottom of the misalignment gap, and the two transparent soft curtains 61 are located on both sides of the misalignment gap.

[0035] In a preferred embodiment, the model box includes a fixed frame and transparent plates filled on the side parts of the fixed frame. The transparent soft curtains are all made of PVC material. The side plates of the model box are all transparent protective glasses, enabling the test personnel to observe the states of the test soil body and the experimental model in the simulation area.

[0036] In a preferred embodiment, the test model 7 is a three-span simply supported beam bridge model, which includes a bridge deck and support beams 71. The support beams 71 are supported on the test soil body, and the bridge deck is supported on the support beams. Fixed piles 72 are also provided below the support beams 72, and the fixed piles 72 are inserted into the test soil body. The pressure sensors and displacement sensors are both attached to the fixed piles 72.

[0037] In a preferred embodiment, a monitoring camera 8 is further included. The monitoring camera 8 faces the two model boxes, and the monitoring camera 8 is used to take test images.

[0038] Reference Figure 3 , in a preferred embodiment, the driving module includes a transverse moving cylinder 3 and a longitudinal moving cylinder 31. Both ends of the transverse moving cylinder 3 and the longitudinal moving cylinder 31 are respectively rotatably connected to the test bench 1 and the side surface of the driving slide 2. The transverse moving cylinder 3 and the longitudinal moving cylinder 31 are vertically arranged. By the mutual cooperation of the transverse moving cylinder 3 and the longitudinal moving cylinder 31, the moving direction and position of the driving slide 2 and the misaligned model box 5 can be controlled. The simulation test device can also control the displacement of the misaligned model box 5, so as to generate a misaligned gap with a predetermined misalignment angle of the test soil body.

[0039] Specifically, define the reverse direction of the model box length as the X-axis direction and the width direction of the model box as the Y-axis direction. Then, operate the driving module to apply displacement to the dislocation plate model 5, causing the dislocation plate model box to dislocate in the specified direction, thereby driving the test soil mass to generate a dislocation gap 73. Moreover, the dislocation angle θ of the dislocation gap 73 and the displacement (x, y) of the dislocation plate model 5 have the following relationship:

[0040]

[0041] For example, the transverse translation cylinder 3 drives the dislocation model box 5 to move 20 mm, and the longitudinal translation cylinder 31 drives the dislocation model box 5 to move 20 mm, 60 mm. At this time, the simulated dislocation angle θ required for the test is 71.6°. This device can study the influence of the dislocation gap 73 on the test model 7 at different dislocation angles.

[0042] In a preferred embodiment, the test device further includes a drive control device. The drive control device is simultaneously connected to the transverse translation cylinder 3 and the longitudinal translation cylinder 31. The drive control device is used to control the telescopic speed of the transverse translation cylinder 3 and the longitudinal translation cylinder 31, thereby controlling the moving speed and direction of the drive slide 2, and further controlling the displacement of the dislocation plate model 5.

[0043] The present invention also includes a strike-slip fault simulation test method for generating oblique fractures. This method uses the above-mentioned strike-slip fault simulation test device for generating oblique fractures. The method includes the following steps:

[0044] S1: Fabricate a test model 7 according to the test requirements, determine the fault angle, and prepare the test soil mass;

[0045] S2: Install the test device, evenly lay the prepared test soil mass in the simulation area, attach sensors to the test model 7, and install the test model 7 in the test soil mass;

[0046] S3: Set up a monitoring camera 8 to capture test images;

[0047] S4: Control the driving module to drive the slide 2 to slide on the test bench 1, causing the dislocation model box 5 to move relative to the fixed model box 4 along a predetermined trajectory, thereby causing the test soil mass in the simulation area to dislocate until a through crack with a predetermined dislocation angle θ is formed in the test soil mass;

[0048] S5: Record the test images and the test data collected by the sensors.

[0049] In this article, the front, back, up, down and other orientation words are defined based on the positions of the components in the drawings and the positions of the components relative to each other, only for the sake of clarity and convenience in expressing the technical solution. It should be understood that the use of the orientation words should not limit the scope of protection requested by this application.

[0050] In the case of no conflict, the above-mentioned embodiments and the features in the embodiments in this article may be combined with each other.

[0051] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A strike-slip fault simulation test device for generating oblique fractures, characterized in that, It includes a test bench, two model boxes, a flexible enclosure component, and a driving component; Connection openings are provided at both ends of the two model boxes, and the connection openings of the two model boxes are arranged opposite to each other; The flexible enclosure component is flexibly connected to the connection openings of the two model boxes, so as to connect the spaces inside the two model boxes to form a simulation area. The simulation area is filled with test soil mass, and a test model for simulating an engineering structure is arranged on the test soil mass. The test model is partially or completely buried in the test soil mass, and pressure sensors and displacement sensors are attached to the test model; The two model boxes are a fixed model box and a staggered model box respectively. The fixed model box is fixedly arranged on the test bench. The driving component includes a driving slide and a plurality of driving modules with different driving directions. The staggered model box is fixed on the driving slide. The driving module is used to drive the driving slide to slide on the test bench, so that the test soil mass in the fixed model box is displaced relative to the test soil mass in the fixed model box.

2. The strike-slip fault simulation test device for generating oblique fractures according to claim 1, wherein, The flexible enclosure component includes geotextile and two transparent soft curtains. Both ends of the geotextile and the two transparent soft curtains are connected between the connection openings of the fixed model box and the staggered model box. The connection openings of the fixed model box and the staggered model box are arranged at intervals with a staggered gap. The geotextile is at the bottom of the staggered gap, and the two transparent soft curtains are on both sides of the staggered gap.

3. The strike-slip fault simulation test device for generating oblique fractures according to claim 1, wherein, The model box includes a fixed frame and transparent plates filled on the side and bottom of the fixed frame.

4. The strike-slip fault simulation test device for generating oblique fractures according to claim 1, characterized in that, The test model is a three-span simply supported beam bridge model.

5. A strike-slip fault simulation test device for generating oblique fractures, characterized in that, The three-span simply supported beam bridge model includes a bridge deck and support beams. The support beams are supported on the test soil mass, the bridge deck is supported on the support beams, and fixed piles are also provided below the support beams. The fixed piles are inserted into the test soil mass.

6. The strike-slip fault simulation test device for generating oblique fractures according to claim 5, characterized in that, Both the pressure sensors and the displacement sensors are attached to the fixed piles.

7. A strike-slip fault simulation test device for generating oblique fractures, characterized in that, It further includes a monitoring camera. The monitoring camera is facing the two model boxes, and the monitoring camera is used to take test images.

8. A strike-slip fault simulation test device for generating oblique fractures, characterized in that, The driving module includes a transverse moving cylinder and a longitudinal moving cylinder. Both ends of the transverse moving cylinder and the longitudinal moving cylinder are respectively rotatably connected to the test bench and the side of the driving slide. The transverse moving cylinder and the longitudinal moving cylinder are vertically arranged.

9. The strike-slip fault simulation test device for generating oblique fractures according to claim 6, characterized in that, It further includes a driving control device. The driving control device is connected to the transverse moving cylinder and the longitudinal moving cylinder at the same time. The driving control device is used to control the telescopic speed of the transverse moving cylinder and the longitudinal moving cylinder, so as to control the moving speed and direction of the driving slide.

10. A method for simulating strike-slip faults that generate oblique ruptures, characterized in that, This method uses the strike-slip fault simulation test device for generating oblique fractures described in any one of claims 1-9. This method includes the following steps: S1: Make a test model according to the test requirements and prepare the test soil mass; S2: Install the test device, evenly lay the prepared test soil mass in the simulation area, attach sensors to the test model, and install the test model in the test soil mass; S3: Set up the monitoring camera to take test images; S4: Control the driving module, drive the driving slide to slide on the test bench, so that the staggered model box moves relative to the fixed model box along a predetermined trajectory, so that the test soil mass in the simulation area is displaced until a through crack with a predetermined displacement angle is formed in the test soil mass; S5: Record the test images and the test data collected by the sensors.

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