Testing device for simulating karst collapse under action of railway vibration

Abstract

The invention provides a test device for simulating karst collapse under the action of railway vibration. The device comprises a karst model box, an excitation system, a rainfall system, a monitoring system and a data acquisition and analysis system, the karst model box comprises a concrete masonry, a simulated soil layer and a simulated railroad bed, a cavity and a channel are formed in the concrete masonry, a filter screen is arranged in the cavity, and a retractable door is arranged at an opening of the channel; the vibration excitation system comprises a vibration exciter and a steel plate and simulates railway vibration; the rainfall system comprises a bracket, a water tank, nozzles, a water pump, a valve and a filter box; the monitoring system comprises an acceleration sensor, a soil pressure sensor, a vibration sensor, a displacement sensor, a pore water pressure gauge, a water meter and a camera; and the data acquisition and analysis system comprises a data acquisition instrument and a computer. According to the device, different working conditions are designed from the aspects of dynamic load, rainfall condition, soil hole number, soil hole burial depth and soil hole diameter, and the soil dynamic response and karst collapse mechanism under the action of train vibration load are explored.

Description

Technical Field

[0001] The invention relates to the technical field of karst collapse simulation equipment, in particular to a test device for simulating karst collapse under the action of railway vibration. Background Art

[0002] Karst collapse, a major geological hazard in karst regions, has become a major engineering geological issue facing high-speed railway planning and construction due to its hidden and sudden nature. During railway operation, karst collapse has two primary impacts: first, it damages the roadbed, posing a threat to railway operation safety; second, it causes bridge pier foundations to sink and damage, impacting traffic safety.

[0003] At present, existing technologies at home and abroad focus on the vibration damage of blasting vibration to rock and soil. The research on the propagation mode of train vibration is also mostly targeted at track structures or structures such as bridge piers and tunnels, which are used to analyze track vibration reduction, environmental noise reduction, and stability analysis of the surrounding rock of bridge piers and tunnels. However, there is a lack of systematic research on the karst collapse disaster mechanism caused by the cumulative effect of low-frequency and low-amplitude vibrations generated by high-speed trains and heavy-load trains during operation. There is a lack of engineering geological collapse models under the action of train vibration characterized by the typical geology of karst areas and model test equipment that can simulate multiple working conditions.

[0004] A simulation test device used in the prior art to simulate karst collapse caused by subway vibration in karst areas is composed of an electric vibrator, an external box, side walls, a bottom plate, a base, a flexible rod, a pad, and a measurement system. The horizontal vibrator can be fixed by the external box and the vertical vibrator can be fixed by the base on the ground, and connected to the inside of the model box through the pad of the model box to achieve horizontal and vertical vibrations. There is a rigid connection between the base and the vibrator, and between the external box and the vibrator. The frequency and amplitude of the vibrator are adjusted externally, and the force is transmitted to the corresponding flexible rod, and then to the pad of the corresponding level; the vibration is transmitted to the soil of the model box through the pad to achieve horizontal and vertical vibration of the model box by the vibrator.

[0005] Another existing model test device for simulating subway vibration-induced karst overburden collapse in karst areas includes a main structure, an excitation system, and a measurement system. The main structure includes a model box, a simulated subway tunnel, and limestone simulation materials that constitute the underground karst structure, karst cavities, karst funnels, and karst overburden. The excitation system includes an electromagnetic exciter installed in the simulated subway tunnel and an external excitation controller. The measurement system includes an accelerometer, a data acquisition device, a soil weighing device, and a camera. Subway vibration is simulated using the excitation device in the simulated subway tunnel. The vibration acceleration at the karst funnel is measured using an accelerometer. The mass of the fallen soil is measured using a soil weighing device. The surface deformation process is observed based on video recordings.

[0006] The disadvantages of the above-mentioned prior art simulation test device for karst collapse under railway vibration include:

[0007] The karst structure design in existing karst collapse model experimental devices is rigid, mostly using prefabricated cavities or single cave structures, which cannot dynamically adjust the cavity burial depth, size and spatial distribution; the multi-physical field coupling mechanism is weak, and there is a lack of intelligent vibration-seepage coordinated control systems, which cannot simulate the dynamic relationship between continuous vibration and water-rock interaction during railway operation.

[0008] The experimental repeatability of existing karst collapse model experimental devices is poor. Traditional devices mostly rely on destructive structures, and the entire components need to be replaced during reconstruction, resulting in high costs and long cycles. Summary of the Invention

[0009] The embodiment of the present invention provides a test device for simulating karst collapse under the action of railway vibration, so as to effectively explore the collapse mechanism in the dynamic process of karst collapse affected by railway vibration.

[0010] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions.

[0011] A test device for simulating karst collapse under railway vibration, comprising: a karst model box, a vibration excitation system, a rainfall system, a monitoring system, and a data acquisition and analysis system;

[0012] The karst model box includes a concrete masonry, a simulated soil layer and a simulated railway roadbed. A cavity simulating a karst structure and a passage connecting the cavity are provided in the concrete masonry. A filter is provided in the cavity, and a telescopic door is provided at the opening of the passage.

[0013] The vibration excitation system includes a vibration exciter and a steel plate to simulate railway vibration;

[0014] The rainfall system includes a bracket, a water tank, a sprinkler, a water pump, a valve and a filter box;

[0015] The monitoring system includes an acceleration sensor, an earth pressure sensor, a vibration sensor, a displacement sensor, a pore water pressure gauge, a water meter and a camera;

[0016] The data acquisition and analysis system includes a data acquisition instrument and a computer.

[0017] Preferably, the dimensions of the karst model box are 1.8 m long × 0.6 m wide × 1.3 m high, with transparent glass panels on all four sides and a reinforced concrete slab on the bottom.

[0018] Preferably, the dimensions of the concrete masonry are 0.6m long × 0.6m wide × 0.3m high, with a cavity and a channel simulating karst in the middle, a transverse filter screen is provided in the middle of the cavity, and a telescopic door with adjustable opening size is provided at the opening of the channel. The telescopic door is used to simulate different sizes of soil holes. The simulated soil layer is soil taken from the actual karst area, and the filling is carried out by layered filling and layered compaction method; the simulated railway roadbed is an accumulation body obtained by scaling down according to the actual situation of the high-speed railway, the accumulation body thickness is 0.1m, and the slope of the side slopes on both sides is 1:1.5.

[0019] Preferably, the steel plate in the excitation system is placed above the simulated railway roadbed, and the vibrator in the excitation system is placed in the middle position above the steel plate. The vibration time and vibration load of the vibrator are controlled to simulate train vibrations in different situations.

[0020] Preferably, the bracket in the rainfall system is used to install and fix the sprinkler head, and is installed on the upper part of the karst model box through a slot. The water tank is placed on one side of the karst model box to provide a water source; the filter box is installed on the right side of the bottom of the water tank, and an inverted filter layer is installed between the filter box and the water tank. The inverted filter layer is connected to the karst model box through an outlet pipe, so that the discharged water enters the water tank, and the water in the water tank will not flow into the karst model box; the water pump is installed on the upper part of the water tank; the water inlet valve is installed on the upper water pipe, and the drain valve is installed on the outlet pipe to control rainfall and drainage respectively.

[0021] Preferably, the acceleration sensor, soil pressure sensor, displacement sensor and pore water pressure gauge in the monitoring system are all buried in the simulated soil layer to monitor the soil vibration, soil pressure, displacement deformation and pore water pressure changes under different working conditions; the vibration sensor is placed on the right side of the simulated railway roadbed to monitor the surface vibration frequency; the water meter is connected to the water pipe to control the simulated rainfall intensity; one of the two cameras is installed at the upper left corner of the bracket to shoot high-definition changes on the soil surface, and the other is set on the front side of the simulation box to record the soil collapse process.

[0022] Preferably, the data acquisition instrument in the data acquisition and analysis system is connected to the acceleration sensor, soil pressure sensor, displacement sensor, vibration sensor and pore water pressure gauge for collecting various monitoring data; the computer is connected to the data acquisition instrument and the camera for storing and analyzing data, and the soil vibration, soil pressure, displacement deformation and pore water pressure changes inside the soil, the vibration propagation on the soil surface and the soil collapse are observed through the computer, the influence of soil hole size, rainfall and vibration on karst collapse is analyzed, and the dynamic response of soil under the action of train vibration load and the karst collapse mechanism are explored.

[0023] It can be seen from the technical solutions provided by the above-mentioned embodiments of the present invention that the present invention proposes a test device for simulating karst collapse under the action of railway vibration, which can design different working conditions from the aspects of dynamic load, rainfall conditions, number of soil holes, soil hole burial depth and soil hole diameter, and better simulate karst collapse from a certain variable or multiple variable perspectives, and explore the dynamic response of soil and the karst collapse mechanism under the action of train vibration load.

[0024] Additional aspects and advantages of the present invention will be set forth in part in the following description, will become apparent from the following description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 any creative work.

[0026] Figure 1 A schematic diagram of the internal cross-sectional structure of a test device for simulating karst collapse under railway vibration provided by an embodiment of the present invention;

[0027] Figure 2 A schematic diagram of the main structure of a test device for simulating karst collapse under railway vibration provided by an embodiment of the present invention;

[0028] Figure 3 A schematic diagram of a top view of a test device for simulating karst collapse under railway vibration provided by an embodiment of the present invention;

[0029] Figure 4 A schematic diagram of a cross-sectional structure of a concrete masonry provided by an embodiment of the present invention;

[0030] Figure 5 A schematic diagram of a perspective structure of a concrete masonry provided by an embodiment of the present invention;

[0031] Figure 6 A schematic diagram of the internal cross-sectional structure of a test device provided by an embodiment of the present invention when the depth of a soil hole is used as a variable;

[0032] In the figure: 1-karst cavity; 2-filter screen; 3-telescopic door; 4-concrete masonry; 5-simulated soil layer; 6-pore water pressure gauge; 7-transparent glass plate; 8-soil pressure sensor; 9-displacement sensor; 10-acceleration sensor; 11-vibration sensor; 12-simulated railway roadbed accumulation; 13-steel plate; 14-vibrator; 15-bracket; 16-sprinkler; 17-camera; 18-water meter; 19-water supply pipe; 20-cage; 21-water inlet valve; 22-water pump; 23-water tank; 24-filter box; 25-drain valve; 26-outlet pipe; 27-data acquisition instrument; 28-computer; 29-karst channel; 30-filter layer. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below, examples of which 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 only used to explain the present invention, and are not to be construed as limiting the present invention.

[0034] It will be understood by those skilled in the art that, unless expressly stated otherwise, the singular forms "a", "an", "said" and "the" used herein may also include the plural forms. It should be further understood that the term "comprising" used in the description of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, "connected" or "coupled" as used herein may include wireless connections or couplings. The term "and / or" used herein includes any unit and all combinations of one or more associated listed items.

[0035] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the art to which the present invention pertains. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and, unless defined as such herein, will not be interpreted in an idealized or overly formal sense.

[0036] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each embodiment does not constitute a limitation on the embodiments of the present invention.

[0037] An embodiment of the present invention proposes a test device for simulating karst collapse under the action of railway vibration. Through a modular reconfigurable karst network, multi-system collaborative loading and intelligent feedback mechanism, the device explores the collapse mechanism in the dynamic process of karst collapse affected by railway vibration. The device has the advantages of simple structure, reusability and easy operation.

[0038] The embodiment of the present invention provides a test device for simulating karst collapse under railway vibration. Figure 1 As shown, the main view structure is as follows Figure 2 As shown, the top view structure is as Figure 3 The experimental device consists of five parts: karst model box, excitation system, rainfall system, monitoring system and data acquisition and analysis system.

[0039] The karst model box includes a concrete masonry 4, a simulated soil layer 5 and a simulated railway roadbed 12. A cross-sectional structural diagram of a concrete masonry provided by an embodiment of the present invention is shown in FIG. Figure 4 As shown, the perspective structure diagram is as follows Figure 5 A cavity 1 simulating a karst structure and a passage 29 communicating with the cavity 1 are provided in the concrete masonry 4. A filter screen 2 is provided in the cavity, and a telescopic door 3 is provided at the opening of the passage.

[0040] The excitation system includes an exciter 14 and a steel plate 13. The vibration time and vibration load of the exciter are controlled to simulate train vibrations in different situations.

[0041] The rainfall system includes a bracket 15, a water tank 23, a nozzle 16, a water pump 22, a valve, and a filter box 24;

[0042] The monitoring system includes an acceleration sensor 10 , an earth pressure sensor 8 , a vibration sensor 11 , a displacement sensor 9 , a pore water pressure gauge 6 , a water meter 18 , and a camera 17 .

[0043] The data acquisition and analysis system includes a data acquisition instrument 27 and a computer 28 .

[0044] The dimensions of the karst model box are 1.8m long × 0.6m wide × 1.3m high, with transparent glass plates 7 on all four sides and a reinforced concrete plate on the bottom to facilitate observation of soil collapse; the concrete masonry 4 measures 0.6m long × 0.6m wide × 0.3m high, with a cavity 1 and a channel 29 simulating karst in the middle. A transverse filter screen 2 is provided in the middle of the cavity to prevent falling soil from clogging the outlet pipe. A telescopic door 3 with adjustable opening size is provided at the opening of the channel 29 to simulate different soil hole sizes. The maximum opening diameter of the telescopic door 3 is 0.1m; the simulated soil layer 5 is experimental soil obtained by taking soil from an actual karst area and reshaping it in the laboratory. The soil layer is 0.7m thick and is filled in layers by a layered filling and compaction method; the simulated railway roadbed 12 is a pile obtained by scaling down the actual situation of the high-speed railway. The pile is 0.1m thick and the slopes on both sides are 1:1.5.

[0045] The steel plate 13 is placed above the simulated railway roadbed 12; the vibration exciter 14 is placed in the middle position above the steel plate 13, and the vibration time and vibration load of the vibration exciter 14 are controlled to simulate train vibrations in different situations.

[0046] The bracket 15 is used to install and fix the nozzle 16, and is installed on the upper part of the karst model box through the slot 20, with a height of 0.2m; the water tank 23 is placed on one side of the karst model box to provide a water source; the filter box 24 is installed on the right side of the bottom of the water tank 23, and an inverted filter layer 30 is installed between the filter box 24 and the water tank 23. It is connected to the karst model box through the outlet pipe 26, so that the discharged water enters the water tank 23, and the water in the water tank 23 does not flow into the karst model box; the water pump 22 is installed on the upper part of the water tank 23; the water inlet valve 21 is installed on the water pipe 19, and the drain valve 25 is installed on the outlet pipe 26 to control rainfall and drainage respectively.

[0047] The acceleration sensor 10, soil pressure sensor 8, displacement sensor 9 and pore water pressure gauge 6 are all buried in the simulated soil layer 5 to monitor soil vibration, soil pressure, displacement deformation and pore water pressure changes under different working conditions; the vibration sensor 11 is placed on the right side of the simulated railway roadbed 12 to monitor the surface vibration frequency; the water meter 18 is connected to the water supply pipe 19, which can be manually read to control the simulated rainfall intensity; the two cameras 17, one is installed in the upper left corner of the bracket, which can capture high-definition changes on the soil surface, and the other is set on the front side of the simulation box to record the soil collapse process.

[0048] The data acquisition instrument is connected to the acceleration sensor 10, the earth pressure sensor 8, the displacement sensor 9, the vibration sensor 11 and the pore water pressure meter 6 for collecting various monitoring data; the computer is connected to the data acquisition instrument 27 and the camera 17 for storing and analyzing data.

[0049] The specific implementation method of the model test using the above-mentioned test device for simulating karst collapse under railway vibration is as follows:

[0050] The internal cross-sectional structure diagram of a test device provided by an embodiment of the present invention when the depth of the soil hole is used as a variable is as follows: Figure 6 As shown in the figure, this embodiment uses different opening sizes of soil holes as variables. First, three concrete masonry units 4 are placed in a karst model box. Then, simulated soil is filled and compacted in layers. During the filling process, corresponding sensors are placed at the designed positions. A pile 12 simulating a railway roadbed is built on top of the simulated soil layer 5, and a steel plate 13 and an exciter 14 are placed on it. Several vibration sensors 11 are placed on the right side of the pile. Water is poured into a water tank 23 to a certain height, a water pump 22 is installed, and a bracket 15 is fixed to the slot 20 on the karst model box. A water pipe 19 and several nozzles 16 are tied to the bracket 15. A water meter 18 and a camera 17 are fixed. The filter box 24 and the three concrete masonry units 4 are connected via a water outlet pipe 26. The monitoring equipment is connected to a data acquisition device 27, and the data acquisition device 27 and the camera 17 are connected to a computer 28.

[0051] Connect all monitoring equipment to a power source. Turn on the vibrator 14 and open the water inlet valve 21. Simulate different train loads by adjusting the vibration time and load of the vibrator 14. Adjust the rainfall amount based on the water meter 18 reading to simulate different rainfall intensities. Adjust the size of the telescopic door 3 on the concrete masonry 4 to simulate different soil hole sizes. During the experiment, use a computer 28 to observe soil vibration, soil pressure, displacement deformation, pore water pressure changes within the soil, vibration propagation on the soil surface, and soil collapse. This allows analysis of the influence of soil hole size, rainfall, and vibration on karst collapse, and explores the dynamic response of the soil under train vibration loads and the mechanism of karst collapse.

[0052] In addition, the model test can also use the soil hole burial depth as a variable, and place another concrete masonry on the third concrete masonry on the far right to achieve the purpose of simulating different soil hole burial depths. The specific implementation method is the same as the above example.

[0053] In summary, the present invention provides a test device for simulating karst collapse under railway vibration, which can realize model experiments under various working conditions taking into account railway vibration, rainfall conditions, soil hole burial depth, number of soil holes, and soil hole diameter. At the same time, the experimental equipment is simple, the concrete masonry is reusable, and the handling is convenient, which helps to reduce the test cost and speed up the test progress, and provides a scientific basis for exploring the dynamic response of soil and the karst collapse mechanism under the action of train vibration load.

[0054] The test device for simulating karst collapse under the action of railway vibration proposed in an embodiment of the present invention can design tests under different working conditions from the aspects of dynamic load, rainfall conditions, number of soil holes, soil hole burial depth and soil hole diameter, and explore the collapse mechanism in the dynamic process of karst collapse affected by railway vibration. It has the advantages of simple structure, reusability and easy operation.

[0055] In the embodiment of the present invention, cavities and pipes simulating karst are provided in the middle of the concrete masonry, and the number and burial depth of the soil holes are changed by arranging and stacking the masonry, thereby realizing working conditions that comprehensively consider multiple factors.

[0056] This embodiment of the present invention incorporates a vibration excitation system, a rainfall system, and a monitoring system to investigate the dynamic response of soil and the mechanism of karst collapse under long-term train vibration loads. The simple experimental equipment and reusable, easily handled concrete masonry help reduce testing costs and accelerate testing progress.

[0057] Those skilled in the art will appreciate that the accompanying drawings are merely schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0058] Each embodiment in this specification is described in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the device or system embodiments, since they are basically similar to the method embodiments, the description is relatively simple. For the relevant parts, refer to the partial description of the method embodiments. The device and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. A person of ordinary skill in the art can understand and implement it without making any creative efforts.

[0059] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A test device for simulating karst collapse under railway vibration, characterized in that: include: Karst model box, vibration system, rainfall system, monitoring system and data acquisition and analysis system; The karst model box includes a concrete masonry, a simulated soil layer and a simulated railway roadbed. A cavity simulating a karst structure and a passage connecting the cavity are provided in the concrete masonry. A filter is provided in the cavity, and a telescopic door is provided at the opening of the passage. The vibration excitation system includes a vibration exciter and a steel plate to simulate railway vibration; The rainfall system includes a bracket, a water tank, a sprinkler, a water pump, a valve and a filter box; The monitoring system includes an acceleration sensor, an earth pressure sensor, a vibration sensor, a displacement sensor, a pore water pressure gauge, a water meter and a camera; The data acquisition and analysis system includes a data acquisition instrument and a computer.

2. The device according to claim 1, characterized in that The dimensions of the karst model box are 1.8m long×0.6m wide×1.3m high, with transparent glass plates on four sides and a reinforced concrete plate on the bottom.

3. The device according to claim 1, characterized in that The concrete masonry has dimensions of 0.6m long × 0.6m wide × 0.3m high, with a cavity and channel simulating karst in the middle. A transverse filter is provided in the middle of the cavity, and a telescopic door with adjustable opening size is provided at the opening of the channel. The telescopic door is used to simulate different sizes of soil holes. The simulated soil layer is soil taken from the actual karst area, and the filling is carried out by layered filling and layered compaction method; the simulated railway roadbed is an accumulation body obtained by scaling down according to the actual situation of the high-speed railway. The accumulation body is 0.1m thick, and the slope of the side slopes on both sides is 1:1.

5.

4. The device according to claim 1, characterized in that The steel plate in the excitation system is placed above the simulated railway roadbed, and the vibrator in the excitation system is placed in the middle position above the steel plate. The vibration time and vibration load of the vibrator are controlled to simulate train vibrations in different situations.

5. The device according to claim 1, characterized in that The bracket in the rainfall system is used to install and fix the sprinkler head, and is installed on the upper part of the karst model box through a slot. The water tank is placed on one side of the karst model box to provide a water source; the filter box is installed on the right side of the bottom of the water tank, and an inverted filter layer is installed between the filter box and the water tank. The inverted filter layer is connected to the karst model box through an outlet pipe, so that the discharged water enters the water tank, and the water in the water tank does not flow into the karst model box; the water pump is installed on the upper part of the water tank; the water inlet valve is installed on the upper water pipe, and the drain valve is installed on the outlet pipe to control rainfall and drainage respectively.

6. The device according to claim 1, characterized in that The acceleration sensor, soil pressure sensor, displacement sensor and pore water pressure gauge in the monitoring system are all buried in the simulated soil layer to monitor the soil vibration, soil pressure, displacement deformation and pore water pressure changes under different working conditions; the vibration sensor is placed on the right side of the simulated railway roadbed to monitor the surface vibration frequency; the water meter is connected to the water supply pipe to control the simulated rainfall intensity; one of the two cameras is installed in the upper left corner of the bracket to capture high-definition changes in the soil surface, and the other is set on the front side of the simulation box to record the soil collapse process.

7. The device according to claim 1, characterized in that The data acquisition instrument in the data acquisition and analysis system is connected to the acceleration sensor, soil pressure sensor, displacement sensor, vibration sensor and pore water pressure gauge for collecting various monitoring data; the computer is connected to the data acquisition instrument and camera for storing and analyzing data. The soil vibration, soil pressure, displacement deformation and pore water pressure changes inside the soil, the vibration propagation on the soil surface and the soil collapse are observed through the computer, the influence of soil hole size, rainfall and vibration on karst collapse is analyzed, and the dynamic response of the soil under the action of train vibration load and the karst collapse mechanism are explored.

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