Method and structure for identifying stress concentration of sliding surface in interface type landslide reduced scale model test

Abstract

The invention discloses an interface type landslide reduced scale model test sliding surface stress concentration identification method and structure. The upper covering soil body is arranged on the bed rock, and a sliding interface is formed on the contact surface of the upper covering soil body and the bed rock; the roller is arranged at the sliding interface, one part of the roller is positioned in the overlying soil body, and the other part of the roller is positioned in the bed rock; the protective shell is arranged in the bedrock, the rolling wheel is rotationally installed in the protective shell, and the protective shell isolates the rolling wheel from the bedrock; the monitoring assembly comprises a monitoring module, a controller and a display module, the monitoring module is used for monitoring the rotating speed and the rotating distance of the roller, the controller is used for receiving and processing monitoring information of the monitoring module, and the monitoring information is displayed through the display module. According to the method, the displacement development rule of the sliding interface in the soil body can be observed, the process from non-stress to emergency concentration to stress concentration damage of the soil body at different positions in the sliding interface can be observed from a dynamic angle, and the development condition of the sliding surface of the reduced scale model test can be judged.

Description

Technical Field

[0001] The present invention relates to the technical field of reduced-scale model tests in geotechnical engineering, and particularly to a method and structure for identifying stress concentration on the sliding surface of an interface-type landslide reduced-scale model test. Background Art

[0002] Reduced-scale model tests are important test means for studying the landslide process. The purpose is to use small-scale test components and control the start of the landslide of the reduced-scale model slope during the test. At present, most experts and scholars make the reduced-scale model slope start to slide by artificial precipitation, artificial thrust, vibration table vibration, and changing the slope angle, and then further study the movement and development of the slope.

[0003] Limited by technical equipment, the current focus of observation by most experts and scholars is on the surface of the landslide body after the slope starts to slide, and it is impossible to observe the state of the soil mass in the sliding interface. How to dynamically observe the stress situation of the soil mass in the sliding surface in the reduced-scale model is the problem faced at present. Summary of the Invention

[0004] The present invention provides a method and structure for identifying stress concentration on the sliding surface of an interface-type landslide reduced-scale model test, which can observe the law of displacement development of the sliding interface existing inside the soil mass, observe the process of the soil mass at different positions in the sliding interface from being unloaded to stress concentration and then to stress concentration failure from a dynamic perspective, and further determine the development of the sliding surface of the reduced-scale model test.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions: The stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention includes: Bedrock; Overlying soil mass, disposed on the bedrock, and the contact surface between the overlying soil mass and the bedrock forms a sliding interface; Roller, disposed at the sliding interface, with a part located in the overlying soil mass and the other part located in the bedrock, and the roller can rotate as the overlying soil mass slides; Protective shell, disposed in the bedrock, and the roller is rotatably installed in the protective shell, and the protective shell isolates the roller from the bedrock; Monitoring component, which includes a monitoring module, a controller, and a display module. The monitoring module is used to monitor the rotation speed and rotation distance of the roller, the controller is used to receive and process the monitoring information of the monitoring module, and display it through the display module.

[0006] For the stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention, further, the monitoring module includes a Hall sensor, and the Hall sensor is disposed in the protective shell for monitoring the rotation speed and rotation distance of the roller.

[0007] The stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention. Further, the bedrock and the overlying soil are arranged in the test box.

[0008] The stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention. Further, a casing is installed on the protective shell, and the casing penetrates through the bedrock and exits from the bottom of the test box; a counting line is connected to the roller, and the counting line can be wound around the roller when the roller rotates; the counting line passes through the casing and is connected to the wire reel, and the monitoring module is used to monitor the rotation speed and rotation distance of the wire reel to determine the rotation speed and rotation distance of the roller.

[0009] The stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention. Further, the roller is a high-friction double rubber wheel.

[0010] The stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention. Further, a positioning steel bar is arranged in the casing, one end of the positioning steel bar exits from the bottom of the test box and is provided with a fixing piece, and the fixing piece hooks on the bottom of the test box.

[0011] The stress concentration identification structure for the sliding surface of the interface-type landslide reduced-scale model test of the present invention. Further, the display module includes a display and an indicator light. The display is used to display the rotation speed and rotation distance of the roller. The indicator lights correspond to the rollers one by one. When the monitoring module monitors that the roller rotates, the controller controls the corresponding indicator light to flash. The faster the rotation speed, the faster the flashing frequency of the indicator light.

[0012] A method for identifying the stress concentration of the sliding surface in the interface-type landslide reduced-scale model test of the present invention includes the following steps: S1: According to the position of the sliding interface in the landslide model reduced-scale test, multiple rollers are arranged, and the protective shell is embedded in the bedrock to isolate the roller from the bedrock and only receive the friction of the overlying soil; S2: Gradually apply an external force to the landslide model to initiate the sliding of the overlying soil; S3: Monitor the rotation speed and rotation distance of the roller through the monitoring component, observe the process of the overlying soil at different positions in the sliding interface from being unstressed to stress concentration and then to stress concentration failure, and then judge the development of the sliding surface in the reduced-scale model test.

[0013] The method for identifying the stress concentration of the sliding surface in the interface-type landslide reduced-scale model test of the present invention. Further, a counting line is connected to the roller, a casing is connected to the protective shell, the casing and the protective shell are embedded in the bedrock, and one end of the casing exits from the bottom of the test box. The counting line passes through the casing and is connected to the wire reel outside the test box; the rotation speed and rotation distance of the roller are determined by monitoring the rotation speed and rotation distance of the wire reel through the monitoring component.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The core of this application is to set a large number of rollers in the sliding interface of the scaled model. Its main purpose is to judge the state of the overlying soil mass on the sliding interface in the area where the roller is located according to the rolling length and rotation speed of the rollers distributed at different positions during the sliding process of the overlying soil mass. According to relevant theories, it can be judged that there will be no stress concentration in the area with more sliding deformation and faster deformation speed, while the area with shorter sliding distance or no sliding deformation is the main area to resist the slope from sliding down; 2. The roller device of this application can passively record the deformation displacement length of the sliding surface, and thus can be theoretically converted into an evaluation of the dynamic development and deformation of the soil mass in each area of the sliding interface, and dynamically analyze the range of the area with stress concentration in the sliding interface; 3. This application can judge the nature of the sliding zone in the area where the roller is located according to the rolling distance of the roller, that is, the longer the sliding distance in a certain area indicates that the sliding interface has been formed at that place, and the area without displacement is the stress concentration area, which is the main factor to resist the sliding of the slope body; 4. This application can judge the speed of the sliding surface and the size of the sliding zone area according to the flashing frequency and the number of flashes of the signal lamp; 5. This application can observe the law of the displacement development of the sliding interface existing inside the soil mass, observe the process of the soil mass at different positions in the sliding interface from being unstressed to stress concentration and then to stress concentration failure from a dynamic perspective, and then judge the development of the sliding surface in the scaled model test, solve the problem that it is currently impossible to dynamically observe the stress situation of the soil mass in the sliding surface in the scaled model, and can be used in combination with various types of interface-type landslide scaled model tests to expand the scope of the scaled model test; 6. By setting a display device, the state of each rubber wheel is dynamically displayed by the indicator light. When the deformation length is longer and the deformation rate is faster, the flashing frequency of the indicator light is faster and the number of flashes is more, indicating that the stress concentration state is damaged and the sliding surface is formed; when the indicator light does not flash or the flashing frequency is slower, there is stress concentration in the soil mass area where the rubber wheel is located at this time.

[0015] The present invention will be further described below with reference to the accompanying drawings. Description of the Drawings

[0016] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a structural schematic diagram of the roller of the present invention; Figure 3 It is a schematic diagram of the monitoring component of the present invention.

[0017] Reference Signs: 1. Test box; 2. Bedrock; 3. Overlying soil mass; 4. Roller; 5. Protective shell; 6. Casing; 7. Counting wire; 8. Positioning steel bar; 9. Fixing part; 10. Wire winder; 11. Controller; 12. Indicator light. Detailed implementation mode

[0018] As Figures 1-3 shown, the present invention provides a method and structure for identifying stress concentration on the sliding surface of an interface-type landslide reduced-scale model test.

[0019] Embodiment 1: The structure includes a test box 1, a bedrock 2 arranged in the test box 1, and an overlying soil mass 3 arranged on the bedrock 2. The contact surface between the overlying soil mass 3 and the bedrock 2 forms a sliding interface. Among them, it is defaulted that the bedrock 2 does not deform in the interface-type landslide.

[0020] Rollers 4 are arranged at the sliding interface. A part of the rollers 4 is located in the overlying soil mass 3, and the other part is located in the bedrock 2. The rollers 4 can rotate as the overlying soil mass 3 slides. In the embodiment of the present application, high-friction double rubber wheels are selected for the rollers 4.

[0021] A protective shell 5 is arranged in the bedrock 2. The rollers 4 are rotatably installed in the protective shell 5. The protective shell 5 isolates the rollers 4 from the bedrock 2, so that the rollers 4 are only subjected to the frictional force of the overlying soil mass 3.

[0022] A casing 6 is installed on the protective shell 5. The casing 6 penetrates through the bedrock 2 and exits from the bottom of the test box 1. A counting wire 7 is connected to the rollers 4. The counting wire 7 can be wound around the rollers 4 when the rollers 4 rotate. The counting wire 7 passes through the casing 6 and is connected to the wire winder 10; in addition, a positioning steel bar 8 is arranged in the casing 6. One end of the positioning steel bar 8 exits from the bottom of the test box 1 and is provided with a fixing part 9. The fixing part 9 is in a claw shape and hooks on the bottom of the test box 1.

[0023] In the embodiment of the present application, a monitoring component is further included. The monitoring component includes a monitoring module, a controller 11, and a display module. The monitoring module is used to monitor the rotation speed and rotation distance of the wire winder 10. The controller 11 receives the monitoring information of the monitoring module and displays the rotation speed and rotation distance through the display module. In the embodiment of the present application, the monitoring module is a Hall sensor, and it can also be other forms of sensors with the function of monitoring the rotation speed and rotation distance.

[0024] The display module includes a display and an indicator light 12. Both the display and the indicator light 12 are electrically connected to the controller 11. The display is used to display the rotation speed and rotation distance of the rollers 4; the number and position of the indicator lights 12 correspond one-to-one to the rollers 4. When the monitoring module monitors that the rollers 4 rotate, the controller 11 controls the corresponding indicator lights 12 to blink. The faster the rotation speed, the faster the blinking frequency of the indicator lights 12; at the same time, the range of the sliding area can be judged according to the number of blinks of the indicator lights 12.

[0025] Embodiment 2: The difference from Embodiment 1 is that the monitoring component directly monitors the rotation speed and rotation distance of the roller 4. The monitoring module includes a Hall sensor, which is arranged in the protective shell 5 and used to monitor the rotation speed and rotation distance of the roller 4.

[0026] Embodiment 3: S1: According to the position of the sliding interface in the landslide model scale test, multiple rollers 4 are arranged. The protective shell 5 is pre-embedded in the bedrock 2 to isolate the roller 4 from the bedrock 2, and it is only affected by the frictional force of the overlying soil mass 3. A counting line 7 is connected to the roller 4, and a sleeve 6 is connected to the protective shell 5. The sleeve 6 and the protective shell 5 are pre-embedded in the bedrock 2, and one end of the sleeve 6 passes through the bottom of the test box 1. The counting line 7 passes through the sleeve 6 and is connected to a winch 10 outside the test box 1.

[0027] S2: Gradually apply an external force to the landslide model to initiate the sliding of the overlying soil mass 3.

[0028] S3: Monitor the rotation speed and rotation distance of the roller 4 through the monitoring component, observe the process of the overlying soil mass 3 at different positions in the sliding interface from being unloaded to stress concentration and then to stress concentration failure, and thereby determine the development of the sliding surface in the scale model test.

[0029] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. Interface landslide scale model test sliding surface stress concentration identification structure, characterized in that, Comprising: Bedrock (2); Overlying soil mass (3), disposed on the bedrock (2), and the contact surface between the overlying soil mass (3) and the bedrock (2) forms a sliding interface; Roller (4), disposed at the sliding interface, with a part located in the overlying soil mass (3) and another part located in the bedrock (2), and the roller (4) can rotate as the overlying soil mass (3) slides; Protective shell (5), disposed in the bedrock (2), the roller (4) is rotatably installed in the protective shell (5), and the protective shell (5) isolates the roller (4) from the bedrock (2); Monitoring assembly, which includes a monitoring module, a controller (11) and a display module. The monitoring module is used to monitor the rotation speed and rotation distance of the roller (4), and the controller (11) is used to receive and process the monitoring information of the monitoring module and display it through the display module.

2. The stress concentration identification structure of the sliding surface of the interfacial landslide reduced-scale model test according to claim 1, characterized in that The monitoring module includes a Hall sensor, and the Hall sensor is disposed in the protective shell (5) for monitoring the rotation speed and rotation distance of the roller (4).

3. The stress concentration identification structure of the sliding surface of the interface type landslide scale model test according to claim 1, characterized in that, The bedrock (2) and the overlying soil mass (3) are arranged in a test box (1).

4. The stress concentration identification structure of the sliding surface for the interface type landslide reduced scale model test according to claim 3, characterized in that, A casing (6) is installed on the protective shell (5), and the casing (6) penetrates through the bedrock (2) and exits from the bottom of the test box (1); a counting wire (7) is connected to the roller (4), and the counting wire (7) can be wound around the roller (4) when the roller (4) rotates; the counting wire (7) passes through the casing (6) and is connected to a wire reel (10), and the monitoring module is used to monitor the rotation speed and rotation distance of the wire reel (10) to determine the rotation speed and rotation distance of the roller (4).

5. The stress concentration identification structure of the sliding surface of the interface-type landslide reduced-scale model test according to claim 4, characterized in that, The roller (4) is a high-friction double rubber wheel.

6. The stress concentration identification structure of the sliding surface for the interfacial landslide scaled model test according to claim 4, characterized in that A positioning steel bar (8) is disposed in the casing (6), one end of the positioning steel bar (8) exits from the bottom of the test box (1) and is provided with a fixing member (9), and the fixing member (9) hooks on the bottom of the test box (1).

7. The stress concentration identification structure of the sliding surface of the interfacial landslide reduced-scale model test according to claim 1, characterized in that The display module includes a display and an indicator light (12). The display is used to display the rotation speed and rotation distance of the roller (4). The indicator lights (12) correspond to the rollers (4) one by one. When the monitoring module monitors that the roller (4) rotates, the controller (11) controls the corresponding indicator light (12) to blink, and the faster the rotation speed, the faster the blinking frequency of the indicator light (12).

8. A method for identifying the stress concentration of the slip surface of an interfacial landslide scaled model test by using the structure according to any one of claims 1-7, characterized in that, Including the following steps: S1: According to the position of the sliding interface in the landslide model scale test, multiple rollers (4) are arranged, and the protective shell (5) is pre-buried in the bedrock (2) to isolate the roller (4) from the bedrock (2) and only be subjected to the friction force of the overlying soil mass (3); S2: Gradually apply an external force to the landslide model to cause the overlying soil mass (3) to start to slide; S3: Monitor the rotation speed and rotation distance of the roller (4) through the monitoring assembly, observe the process of the overlying soil mass (3) at different positions in the sliding interface from being unloaded to stress concentration and then to stress concentration failure, and then judge the development of the sliding surface in the scale model test.

9. The method for identifying stress concentration on the sliding surface of the interface-type landslide scaled model test according to claim 8, characterized in that A counting wire (7) is connected to the roller (4), and a sleeve (6) is connected to the protective shell (5). The sleeve (6) and the protective shell (5) are embedded in the bedrock (2), and one end of the sleeve (6) passes through the bottom of the test chamber (1). The counting wire (7) passes through the sleeve (6) and is connected to a wire winder (10) outside the test chamber (1); the rotation speed and rotation distance of the wire winder (10) are monitored by a monitoring component to determine the rotation speed and rotation distance of the roller (4).

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