Soil cave collapse test device

Abstract

The utility model relates to a soil cave collapse test device which comprises a box body, a rock-soil filling space is formed in the box body, and an observation window and a gate with a hole are respectively arranged in the middle of the box body along the vertical direction; the monitoring pipe is horizontally arranged in the box body and supported in the middle of rock soil, and a plurality of section monitoring elements are arranged in the length direction of the monitoring pipe at equal intervals. A cable of each section monitoring element penetrates through the first vertical protection pipe and extends out of the top of the box body; a plurality of first displacement monitoring points are arranged in different layers of the rock soil, and a first displacement probe rod at each first displacement monitoring point extends out of the top of the box body through a second vertical protection pipe and is correspondingly connected with a first displacement meter; and the section monitoring element and the first displacement meter are connected to the acquisition system. According to the utility model, the filling process is accurately controlled, layered filling and compaction are realized, meanwhile, the device has the capability of monitoring soil layer displacement and stress change in real time, and the dynamic process of soil collapse is convenient to observe, so that the simulation fidelity and the research accuracy are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of geotechnical engineering tests, and more specifically to a soil cave collapse test device. Background Art

[0002] In the field of geotechnical engineering, soil cave collapse is a common geological disaster with complex causes, mainly including natural factors and human activities. Natural factors mainly involve the dissolution of groundwater, geological tectonic movement, changes in the physical and chemical properties of soil layers, etc. These factors can lead to the formation and expansion of underground space and eventually cause surface collapse. Human factors mainly refer to various engineering construction activities, such as mining, tunnel excavation, groundwater extraction, etc. These activities may change the original hydrogeological conditions and accelerate the formation and collapse of soil caves.

[0003] Traditional soil cave collapse research mostly relies on on-site investigation and post-analysis, which has limitations. For example, it is difficult to capture dynamic information at the moment of collapse, and it is impossible to accurately measure the changes in the mechanical parameters of the soil before and after the collapse. It is also strictly restricted by time and location, making it difficult to conduct systematic and repeatable experimental research. In addition, since natural soil cave collapse events are often accompanied by suddenness and unpredictability, they pose great challenges to prevention and emergency response.

[0004] In view of the above problems, researchers began to turn to indoor model tests to simulate the soil hole collapse process, hoping to accurately measure and analyze the collapse mechanism by controlling variables. However, early test devices generally had problems such as low simulation accuracy, complex operation, and inconvenient observation, which made it difficult to meet the high standards of scientific research and engineering applications. In particular, there is a lack of effective technical and equipment support for monitoring small deformations in the early stage of soil hole formation, real-time capture of stress distribution during collapse, and evaluation of soil displacement and failure mode after collapse.

[0005] Therefore, how to provide a soil cave collapse test device is a problem that technical personnel in this field need to solve urgently. Utility Model Content

[0006] To this end, the purpose of the utility model is to propose a soil hole collapse test device that can simulate the entire cycle of soil hole collapse, integrate multiple monitoring methods, is easy to operate and intuitive to observe, so as to more deeply explore the physical mechanism of soil hole collapse and provide a scientific basis for the formulation of disaster prediction and prevention and control strategies.

[0007] The utility model provides a soil cave collapse test device, comprising:

[0008] A box body, wherein a rock-soil filling space is formed inside the box body, and an observation window and a gate with an opening are respectively arranged in the middle of the box body along the vertical direction;

[0009] A monitoring pipe, the monitoring pipe is horizontally arranged in the box, supported in the middle of the rock and soil, and has a plurality of cross-section monitoring elements arranged at equal intervals along its length direction;

[0010] A first vertical protective tube, through which the cables of each cross-section monitoring element extend toward the top of the box body;

[0011] A first displacement meter, wherein a plurality of first displacement monitoring points are arranged in different layers of rock and soil, and a first displacement probe rod at each first displacement monitoring point extends to the top of the box through a second vertical protection tube and is correspondingly connected to the first displacement meter;

[0012] The acquisition system, the cross-section monitoring element and the first displacement meter are both connected to the acquisition system.

[0013] Furthermore, a second displacement monitoring point is arranged on the monitoring tube corresponding to each of the cross-section monitoring elements, and a spacing is maintained between the cross-section monitoring element and the second displacement monitoring point. A second probe rod corresponding to the second displacement monitoring point extends upward and passes through the first vertical protective tube to extend to the top of the box body, and is correspondingly connected to a second displacement meter, which is connected to the acquisition system.

[0014] Furthermore, a pair of observation windows are symmetrically provided on the upper part of two opposite walls of the box body, and a pair of gates are symmetrically provided on the lower part. The observation windows are tempered glass windows with observation equidistant lines, and the gates are one-way opening metal doors.

[0015] Furthermore, the monitoring tube is a PE tube, and a plurality of cross-section monitoring elements are arranged on the outer circumference of each cross-section monitoring point thereof, and each second displacement probe rod on the monitoring tube is connected to the monitoring tube via a ball head.

[0016] Furthermore, the cross-section monitoring element is a strain gauge and a conductive film, and the strain gauge and the conductive film are bonded to the outer wall of the monitoring tube.

[0017] Furthermore, the first vertical protection tube and the second vertical protection tube are both polypropylene tubes.

[0018] Furthermore, two steel beams are arranged on the top of the box body, and the two steel beams respectively fix the first displacement meter and the second displacement meter; two ends of the steel beams are fixed to the top of the box body by two G-shaped fixing pressure clamps.

[0019] Furthermore, elevation rulers are provided in the length direction and the height direction of the box.

[0020] Furthermore, the gate and the box body are fixed by plugging and connecting with fixing pins.

[0021] Furthermore, grille reinforcement ribs are arranged on the outer wall of the box body, the grille reinforcement ribs form a plurality of grid shapes, and a ladder is provided on the outside of the box body.

[0022] It can be seen from the above technical scheme that compared with the prior art, the utility model discloses a soil hole collapse test device, which can accurately control the filling process, realize layered filling and compaction, and at the same time has the ability to monitor the displacement and stress changes of soil layers in real time, which is convenient for observing the dynamic process of soil collapse, thereby improving the realism of simulation and the accuracy of research.

[0023] In order to monitor the displacement more accurately, a second displacement meter is connected to the monitoring tube for displacement monitoring near the soil hole, so that the acquisition system can collect more displacement information, obtain the surface settlement displacement of the soil layer monitored by the first displacement meter, and the displacement near the soil hole when it is formed monitored by the second displacement meter, and comprehensively analyze the displacement of the rock and soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0025] Figure 1 A schematic diagram of the structure of a soil cave collapse test device provided by the utility model;

[0026] Figure 2 A schematic diagram of the structure of a soil cave collapse test device provided by the utility model (without showing the observation window);

[0027] Figure 3 A side view of a soil cave collapse test device provided by the utility model;

[0028] Figure 4 for Figure 3 AA section view;

[0029] Figure 5 for Figure 3 BB cross-sectional view. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0031] Since traditional soil cave collapse research mostly relies on on-site investigation and post-analysis, this method has limitations. It is difficult to capture the dynamic information of the collapse moment, and it is impossible to accurately measure the changes in the mechanical parameters of the soil before and after the collapse. It is also strictly restricted by time and location, making it difficult to conduct systematic and repeatable experimental research. In addition, since natural soil cave collapse events are often accompanied by suddenness and unpredictability, they pose great challenges to prevention and emergency response. Early test devices generally have problems such as low simulation accuracy, complex operation, and inconvenient observation, which are difficult to meet the high standards of scientific research and engineering applications.

[0032] In view of this, the utility model provides a soil cave collapse test device, see attached Figure 1 and 2 ,include:

[0033] A box body 100, wherein a rock-soil filling space is formed inside the box body 100, and an observation window 101 and a gate 102 with an opening are respectively arranged in the middle of the box body 100 along the vertical direction;

[0034] A monitoring pipe 200, the monitoring pipe 200 is horizontally arranged in the box 100, supported in the middle of the rock and soil, and a plurality of cross-section monitoring elements 201 are arranged at equal intervals along the length direction thereof;

[0035] A first vertical protection tube 300, through which the cables of each cross-section monitoring element 201 extend toward the top of the box 100;

[0036] A first displacement meter 400, wherein a plurality of first displacement monitoring points are arranged in different layers of rock and soil, and a first displacement probe rod at each first displacement monitoring point extends to the top of the box 100 through a second vertical protection tube 500 and is correspondingly connected to the first displacement meter 400;

[0037] Acquisition system: the cross-section monitoring element 201 and the first displacement meter 400 are both connected to the acquisition system.

[0038] The above-mentioned embodiment can accurately control the filling process, realize layered filling and compaction, and at the same time has the ability to monitor the displacement and stress changes of soil layers in real time, so as to facilitate the observation of the dynamic process of soil collapse, thereby improving the realism of simulation and the accuracy of research.

[0039] Advantageously, see Appendix Figure 3-5A second displacement monitoring point is arranged on the monitoring tube 200 corresponding to each of the cross-section monitoring elements 201, and a spacing is maintained between the cross-section monitoring element 201 and the second displacement monitoring point. The second probe rod corresponding to the second displacement monitoring point extends upward and passes through the first vertical protection tube 300 to extend to the top of the box 100, and is correspondingly connected to the second displacement meter 401, and the second displacement meter 401 is connected to the acquisition system.

[0040] In this embodiment, a second displacement meter is connected to the monitoring tube for displacement monitoring near the soil hole, so that the acquisition system can collect more displacement change information, obtain the soil layer settlement displacement monitored by the first displacement meter, and the displacement change near the soil hole when it is formed and collapsed monitored by the second displacement meter, comprehensively analyze the displacement changes of rock and soil, and further improve the monitoring accuracy.

[0041] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0042] In the embodiment of the utility model, a pair of observation windows 101 are symmetrically arranged on the upper part of two opposite walls of the box body 100, and a pair of gates 102 are symmetrically arranged on the lower part. The observation windows 101 are tempered glass windows with observation equidistant lines 800, and the gates 102 are one-way opening metal doors. The observation windows can be 1m×1m or 1m×2m, and the front and rear observation windows can be made into different sizes according to the usage conditions. The outer side is provided with equidistant observation lines 800 at intervals of 10cm to guide the control of the filling thickness of the soil material.

[0043] In the above embodiments, the monitoring tube 200 is a PE tube, and a plurality of cross-section monitoring elements 201 are arranged on the outer circumference of each cross-section monitoring point thereof. Each second displacement probe on the monitoring tube 200 is connected to the monitoring tube 200 via a ball head.

[0044] Specifically, the monitoring pipe 200 may be 3 m long, 75 mm in diameter, and 3.6 mm thick. A monitoring section may be provided every 0.6 m and connected to the first vertical protection pipe 300.

[0045] In some other embodiments, the cross-section monitoring element 201 is a strain gauge and a conductive film, and the strain gauge and the conductive film are bonded to the outer wall of the monitoring tube 200 .

[0046] Advantageously, the first vertical protection tube 300 and the second vertical protection tube 500 are both polypropylene tubes, which are used to protect the data transmission line and the probe rod from excessive disturbance of the soil.

[0047] Two steel beams 700 are arranged on the top of the box body 100, and the two steel beams 700 respectively fix the first displacement meter 400 and the second displacement meter 401; both ends of the steel beam 700 are fixed to the top of the box body 100 by two G-shaped fixed pressure clamps 701 to ensure structural stability.

[0048] The box 100 is provided with elevation scales in both the length direction and the height direction. It is advantageous to equip the observation window with an elevation scale to help observe the compaction state of the soil and the height of the soil layer.

[0049] In the above embodiments, the gate 102 is fixed to the box 100 by plugging with the fixing pin 103. The gate 102 may have a size of 1m×1m, and has a positioning pin on the outside to control the closing and opening during soil filling.

[0050] Advantageously, the outer wall of the box body 100 is provided with grid reinforcement ribs 900, and the grid reinforcement ribs 900 form a plurality of grid shapes. The grid reinforcement ribs 900 divide the box body 100 into a plurality of 50 cm×50 cm square grids, thereby enhancing the boundary restraint force;

[0051] The outside of the box 100 is equipped with a ladder 104, one on each side of the device, and the top of the ladder 104 is equipped with a limit hook, which is connected to the box to prevent slipping; the ladder is used when filling soil into the box.

[0052] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0053] When the utility model is used:

[0054] Install the ladder on both sides of the box and lock the gate and positioning pins; put rock and soil into the box through the ladder, and tamp the soil when the height of the rock and soil reaches the specified scale of the equidistant observation line;

[0055] When the soil layer height reaches 1 meter, a PE monitoring pipe is laid along the length direction of the rectangular box, and after setting the monitoring point, the data transmission cable and the second displacement probe are led out through the polypropylene protective pipe. The first displacement probe needs to be arranged in different soil layers;

[0056] After completing the installation of cables and monitoring points, continue filling and tamping the soil in layers;

[0057] When the soil layer reaches the top, two G-type fixed pressure clamps are used to clamp a steel beam, with a total of two parallel steel beams, and the first displacement meter and the second displacement meter are installed on the two steel beams respectively;

[0058] Finally, the data acquisition instrument in the collection system was tested by opening the front and rear gates to simulate human digging, and gradually observing the soil hole collapse process, recording the corresponding monitoring data information for analysis.

[0059] In the above embodiments, the coordinated use of the polypropylene protection tube and the PE monitoring tube ensures the accuracy of data collection and the reliability of transmission, and provides key data for soil deformation and stress analysis.

[0060] The setting of front and rear tempered glass observation windows, combined with equidistant observation lines and elevation scales, provides an intuitive visual reference for observing soil changes, facilitating real-time monitoring and recording by scientific researchers.

[0061] The design of the G-type fixed pressure fixture and steel beam ensures the structural stability of the test device during loading and simulated collapse, improving the safety and repeatability of the test.

[0062] The utility model realizes precise control and observation: by setting precise sensors such as displacement meters and strain gauges, the displacement and stress changes of soil layers can be precisely measured to realize quantitative analysis of the collapse process.

[0063] Intuitive visualization: The front and rear tempered glass observation windows, equipped with equidistant observation lines and elevation rulers, make the soil filling status and collapse process clear at a glance.

[0064] Convenient operation: The single-opening gate and positioning pin design facilitates the layered placement and compaction of soil materials, while ensuring the repeatability of the experiment.

[0065] Stable structure: The configuration of steel beams, G-type fixed pressure fixtures, ladders and grid reinforcements ensures the stability and safety of the entire device and is suitable for loading tests of different intensities.

[0066] In the model box test of the embodiment of the utility model, five monitoring sections are set on the PE monitoring pipe at intervals of 0.6 m, and are respectively equipped with conductive films and strain gauges.

[0067] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] The specific layout plan is as follows:

[0069] On the five sections, four monitoring elements are installed at 90° on the top and 270° on the bottom of each section, covering the conductive film and strain gauges in both axial and radial directions.

[0070] In addition, two detection elements are also installed in the 0° and 180° directions of the monitoring tube, including radial conductive films and strain gauges. Considering that the middle section may produce significant deformation during the test and has a higher monitoring value, radial strain gauges and conductive film monitoring elements in each 45° direction are added to this section. All strain gauges and conductive films are subject to real-time data acquisition and monitoring through static strain gauges to accurately record the deformation response of the monitoring tube under stress.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0072] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A soil cave collapse test device, characterized in that: include: A box body (100), wherein a rock-soil filling space is formed inside the box body (100), and an observation window (101) and a gate (102) with an opening are respectively arranged in a vertical direction in the middle of the box body (100); A monitoring pipe (200), the monitoring pipe (200) being arranged horizontally in the box (100), supported in the middle of the rock and soil, and having a plurality of cross-section monitoring elements (201) arranged at equal intervals along its length direction; A first vertical protective tube (300), wherein the cables of each cross-section monitoring element (201) pass through the first vertical protective tube (300) and extend toward the top of the box (100); A first displacement meter (400), wherein a plurality of first displacement monitoring points are arranged in different layers of rock and soil, and a first displacement probe rod at each first displacement monitoring point extends to the top of the box (100) through a second vertical protection tube (500) and is correspondingly connected to the first displacement meter (400); A collection system, the cross-section monitoring element (201) and the first displacement meter (400) are both connected to the collection system.

2. A soil cave collapse test device according to claim 1, characterized in that: A second displacement monitoring point is arranged on the monitoring tube (200) corresponding to each of the cross-section monitoring elements (201), and a spacing is maintained between the cross-section monitoring element (201) and the second displacement monitoring point. A second probe rod corresponding to the second displacement monitoring point extends upward, passes through the first vertical protection tube (300), and extends toward the top of the box (100), and is correspondingly connected to a second displacement meter (401), and the second displacement meter (401) is connected to a collection system.

3. A soil cave collapse test device according to claim 2, characterized in that: A pair of observation windows (101) are symmetrically arranged on the upper part of two opposite walls of the box body (100), and a pair of gates (102) are symmetrically arranged on the lower part; the observation windows (101) are tempered glass windows with observation equidistant lines (800), and the gates (102) are one-way opening metal doors.

4. A soil cave collapse test device according to claim 3, characterized in that: The monitoring tube (200) is a PE tube, and a plurality of cross-section monitoring elements (201) are arranged on the outer circumference of each cross-section monitoring point thereof, and each second displacement probe rod on the monitoring tube (200) is connected to the monitoring tube (200) via a ball head.

5. A soil cave collapse test device according to claim 1, characterized in that: The cross-section monitoring element (201) is a strain gauge and a conductive film, and the strain gauge and the conductive film are bonded to the outer wall of the monitoring tube (200).

6. A soil cave collapse test device according to claim 1, characterized in that: The first vertical protection tube (300) and the second vertical protection tube (500) are both polypropylene tubes.

7. A soil cave collapse test device according to claim 2, characterized in that: Two steel beams (700) are arranged on the top of the box body (100), and the two steel beams (700) respectively fix the first displacement meter (400) and the second displacement meter (401); two ends of the steel beam (700) are fixed to the top of the box body (100) by two G-shaped fixing pressure clamps (701).

8. A soil cave collapse test device according to claim 1, characterized in that: The box (100) is provided with elevation rulers in both the length direction and the height direction.

9. A soil cave collapse test device according to claim 1, characterized in that: The gate (102) and the box body (100) are plugged and fixed via a fixing pin (103).

10. A soil cave collapse test device according to claim 1, characterized in that: The outer wall of the box body (100) is provided with grille reinforcement ribs (900), the grille reinforcement ribs (900) form a plurality of grid shapes, and the outside of the box body (100) is equipped with a ladder (104).

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