Karst collapse multi-parameter monitoring and early warning test system

Abstract

The invention discloses a karst collapse multi-parameter monitoring and early warning test system, including a karst collapse simulation system, a groundwater parameter monitoring system and a soil deformation monitoring system, wherein the karst collapse simulation system includes a box and a karst pipeline simulation system, the box is divided into three parts: a water inlet box, a soil box and a drainage box, and a through hole is provided on the bottom end surface of the soil box; the karst pipeline simulation system is established according to the actual situation of the exploration or the karst collapse example, including a simulated karst cave and each simulated karst pipeline connected thereto, an inlet and outlet pipe, and the simulated karst cave is connected to the through hole on the soil box through the simulated karst pipeline; the groundwater parameter monitoring system includes various monitoring devices for monitoring groundwater index parameters, and the probes of each monitoring device are respectively placed at the pre-set measurement positions in the karst pipeline simulation system; the soil deformation monitoring system includes an optical fiber and an optical fiber strain monitoring device arranged in the original soil sample. The system of the invention has a high early warning accuracy for karst collapse.

Description

Technical Field

[0001] The invention relates to a karst collapse multi-parameter monitoring and early warning test system, belonging to the technical field of karst collapse geological disaster prevention and control. Background Art

[0002] Karst collapse is one of the main geological disasters in karst areas. It is characterized by concealment, suddenness, and recurrence. Monitoring and early warning of karst collapse is an important link in the prevention and control of karst collapse, and it is also one of the world-class technical problems that have not been overcome in the current field of earth science. The formation of karst collapse is the result of the combined effects of rock, soil, water and human activities. There are many influencing factors, and the evolution process is very complex, including groundwater erosion, chemical dissolution, vacuum erosion, mechanical vibration and other effects. Each effect will cause deformation and damage to the rock and soil, and is accompanied by geological phenomena. In the process of groundwater erosion, parameters such as groundwater fluctuation amplitude, frequency, water flow velocity and turbidity will reflect the deformation and damage of the rock and soil; in the process of chemical dissolution, parameters such as anions, cations and total dissolved solids (TDS) of soil and groundwater will change significantly; in the process of mechanical vibration, parameters such as vibration amplitude, frequency and vibration mode also have a good correspondence with the deformation of the rock and soil. Therefore, in order to improve the accuracy and level of karst collapse monitoring and early warning, it is necessary to carry out multi-parameter monitoring and early warning work. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a karst collapse multi-parameter monitoring and early warning test system with higher early warning accuracy.

[0004] The karst collapse multi-parameter monitoring and early warning test system of the present invention comprises a karst collapse simulation system, a groundwater parameter monitoring system and a soil deformation monitoring system, and is characterized by:

[0005] The karst collapse simulation system comprises a box and a karst pipeline simulation system, wherein:

[0006] Two permeable baffles are arranged in the box body, dividing the box body into three parts: a water inlet box, a soil box and a drainage box, wherein the soil box is located between the water inlet box and the drainage box, and the water inlet box, the soil box and the drainage box realize mutual circulation of liquid through the permeable holes on the permeable baffles; the soil box is used to fill the original soil sample, and a through hole is opened on the bottom end surface of the soil box;

[0007] The karst pipeline simulation system is established according to the actual situation of the exploration or the karst collapse example, and mainly includes a simulated cave, each simulated karst pipeline connected to the simulated cave, and a water inlet pipe and a drain pipe for providing water inlet and water outlet for the simulated karst pipeline. Valves and pressure gauges are arranged on the water inlet pipe and the drain pipe. Valves are arranged on each simulated karst pipeline as needed to control the on and off of water flow; the simulated cave is connected to the through hole on the bottom end surface of the soil box through the simulated karst pipeline;

[0008] The groundwater parameter monitoring system comprises a groundwater level monitoring device, a groundwater flow rate monitoring device, a groundwater turbidity monitoring device and a groundwater chemical monitoring device, and the probes of each monitoring device are respectively placed at the pre-set measurement positions in the karst pipeline simulation system;

[0009] The soil deformation monitoring system comprises an optical fiber arranged in an original soil sample in a soil box and an optical fiber strain monitoring device for monitoring the strain of the optical fiber.

[0010] In the above technical scheme, the groundwater parameter monitoring system preferably includes two sets of groundwater level monitoring devices, two sets of groundwater flow rate monitoring devices, one set of groundwater turbidity monitoring devices and one set of groundwater chemical monitoring devices, wherein the probe of one set of groundwater level monitoring devices and the probe of groundwater flow rate monitoring devices are arranged in a simulated karst pipeline at the same horizontal position as the simulated cave, while the probe of the groundwater turbidity monitoring device and the probe of the groundwater chemical monitoring device are both arranged in the simulated karst pipeline below the probe of the above-mentioned groundwater level monitoring device and the probe of the groundwater flow rate monitoring device; the probe of another set of groundwater level monitoring device and the probe of the groundwater flow rate monitoring device are arranged before the outlet end of the drainage pipe. By setting probes of groundwater level monitoring device and groundwater flow rate monitoring device in the simulated karst pipeline at the same horizontal position as the simulated cave, various monitoring data such as water pressure and water flow rate on the same runoff as the simulated cave can be effectively monitored; and the probe of groundwater turbidity monitoring device and the probe of groundwater chemistry monitoring device are both set in the simulated karst pipeline below the probe of groundwater level monitoring device and the probe of groundwater flow rate monitoring device (that is, set in the simulated karst pipeline deeper from the ground surface than the probe of groundwater level monitoring device and the probe of groundwater flow rate monitoring device) to measure the turbidity, TDS, conductivity, various ion concentrations and other related indicators of water body after being affected by rock dissolution and soil deformation and damage, for subsequent comparative analysis.

[0011] In the above technical scheme, the groundwater level monitoring device, groundwater flow rate monitoring device, groundwater turbidity monitoring device and groundwater chemical monitoring device are conventional choices in the prior art. Specifically, the groundwater level monitoring device can be a 3001-type Edge water level recorder from Solinst, Canada; the groundwater flow rate monitoring device can be a 600-type acoustic Doppler flowmeter from Flowstar, USA; the groundwater turbidity monitoring device can be a Turb2000-type online turbidity analyzer from WTW, Germany; and the groundwater chemical monitoring device can be a MS6100-type multi-parameter water quality online analyzer from HACH, USA.

[0012] In the above technical solution, the number of optical fibers is set according to needs, and they are buried in the original soil samples at different depths in the soil box to obtain deformation data of the original soil samples at different positions; the optical fiber strain monitoring device can specifically be the BOTDR optical fiber strain tester of Japan Ando Company.

[0013] In the above technical scheme, in order to adjust the pressure difference in and out of the karst pipeline simulation system, the drainage pipe is preferably arranged longitudinally, and a plurality of branch drainage pipes are arranged on it, and valves and pressure gauges are arranged on each branch drainage pipe. The pressure difference in and out of the karst pipeline simulation system can be adjusted by controlling different branch drainage pipes to drain water.

[0014] Since the karst collapse multi-parameter monitoring and early warning test system of the present invention is used for actual monitoring, the karst pipeline simulation system therein is established according to the actual situation of the exploration or the karst collapse example. In a specific implementation example, the karst pipeline simulation system includes a simulated cave, a first simulated karst pipeline connected to the simulated cave, a second simulated karst pipeline, a third simulated karst pipeline and a fourth simulated karst pipeline, a sixth simulated karst pipeline connected to the second simulated karst pipeline, and a seventh simulated karst pipeline connected to the second simulated karst pipeline; wherein,

[0015] The first simulated karst pipeline is connected to the through hole on the bottom end surface of the soil box, and the second simulated karst pipeline and the third simulated karst pipeline are at the same horizontal position as the simulated cave;

[0016] The second simulated karst pipeline, the third simulated karst pipeline and the fourth simulated karst pipeline are connected by

[0017] A fifth simulated karst pipeline forms a loop, and the fifth simulated karst pipeline is located below the second simulated karst pipeline and the third simulated karst pipeline;

[0018] The sixth simulated karst pipeline is parallel to the first simulated karst pipeline, and the seventh simulated karst pipeline is parallel to the second simulated karst pipeline and the third simulated karst pipeline;

[0019] The third simulated karst pipeline is connected to the water inlet pipe, and the seventh simulated karst pipeline is connected to the drainage pipe;

[0020] The second simulated karst pipeline, the third simulated karst pipeline and the fourth simulated karst pipeline are each provided with a valve; the fifth simulated karst pipeline is provided with two valves, and the two valves are respectively provided near the connection with the second simulated karst pipeline and near the connection with the third simulated karst pipeline.

[0021] In the above-mentioned specific implementation example, one set of probes of the groundwater level monitoring device and the groundwater flow rate monitoring device in the groundwater parameter monitoring system are arranged in the third simulated karst pipeline, another set of probes of the groundwater level monitoring device and the groundwater flow rate monitoring device are arranged in the seventh simulated karst pipeline, and the probes of the groundwater turbidity monitoring device and the groundwater chemistry monitoring device are arranged in the fifth simulated karst pipeline.

[0022] Compared with the prior art, the system of the present invention obtains multiple index parameters by multi-directionally monitoring the deformation and damage of the soil and the impact of the deformation and damage of the soil on underground caves, karst pipes and groundwater. After further analysis, a comprehensive early warning threshold can be obtained to achieve early warning and forecasting of karst collapse. In addition, the system structure of the present invention is simplified, and more index parameters can be obtained, thereby greatly improving the early warning accuracy of karst collapse monitoring and early warning work, which is of great significance to improving the level of karst collapse prevention and control, and enriching and improving the karst collapse research and application system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of an implementation method of the karst collapse multi-parameter monitoring and early warning test system of the present invention.

[0024] The numbers in the figure are:

[0025] 1 drainage box, 2 permeable baffle, 3 soil box, 4 water inlet box, 5 groundwater parameter monitoring system, 6 optical fiber strain monitoring device, 7 valve, 8 pressure gauge, 9 water inlet pipe, 10 probe of groundwater level monitoring device, 11 probe of groundwater flow rate monitoring device, 12 the third simulated karst pipeline, 13 probe of groundwater chemical monitoring device, 14 simulated cave, 15 fourth simulated karst pipeline, 16 fifth simulated karst pipeline, 17 probe of groundwater turbidity monitoring device, 18 bracket, 19 second simulated karst pipeline, 20 first simulated karst pipeline, 21 through hole, 22 optical fiber, 23 original soil sample, 24 sixth simulated karst pipeline, 25 seventh simulated karst pipeline, 26 drainage pipe, 27 branch drainage pipe. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings to provide a better understanding of the content of the present invention, but the present invention is not limited to the following embodiments.

[0027] like Figure 1 As shown, the karst collapse multi-parameter monitoring and early warning test system of the present invention includes a karst collapse simulation system, a groundwater parameter monitoring system 5 and a soil deformation monitoring system, and is characterized by:

[0028] The karst collapse simulation system comprises a box and a karst pipeline simulation system, wherein:

[0029] The box is an open box, fixed on the bracket 18, and two permeable baffles 2 are arranged in the box to divide the box into three parts: a water inlet box 4, a soil box 3 and a drainage box 1, wherein the soil box 3 is located between the water inlet box 4 and the drainage box 1, and the water inlet box 4, the soil box 3 and the drainage box 1 realize the mutual circulation of liquid through the permeable holes on the permeable baffles 2; the soil box 3 is used to fill the original soil sample 23, and a through hole 21 is opened on the bottom end surface of the soil box 3, and the through hole 21 is used to simulate the opening of the cave;

[0030] The karst pipeline simulation system mainly includes a simulated cave 14, simulated karst pipelines connected to the simulated cave 14, and an inlet pipe 9 and a drain pipe 26 for providing inlet and outlet water for the simulated karst pipelines, wherein:

[0031] The water inlet pipe 9 is provided with a valve 7 and a pressure gauge 8;

[0032] The drainage pipe 26 is arranged longitudinally, and three branch drainage pipes 27 are arranged on it. A valve 7 and a pressure gauge 8 are arranged on each branch drainage pipe 27. The pressure difference in and out of the karst pipeline simulation system is adjusted by controlling the drainage of different branch drainage pipes 27.

[0033] The simulated karst pipelines connected to the simulated cave 14 include a first simulated karst pipeline 20, a second simulated karst pipeline 19, a third simulated karst pipeline 12 and a fourth simulated karst pipeline 15 connected to the simulated cave 14, a sixth simulated karst pipeline 24 connected to the second simulated karst pipeline 19, and a seventh simulated karst pipeline 25 connected to the second simulated karst pipeline 19; wherein the first simulated karst pipeline 20 is connected to the through hole 21 on the bottom end surface of the soil box 3, and the second simulated karst pipeline 19 and the third simulated karst pipeline 12 are at the same horizontal position as the simulated cave 14; the second simulated karst pipeline 19, the third simulated karst pipeline 12 and the fourth simulated karst pipeline 15 form a loop through the fifth simulated karst pipeline 16, and the seventh simulated karst pipeline 25 is connected to the second simulated karst pipeline 19. The fifth simulated karst pipeline 16 is located below the second simulated karst pipeline 19 and the third simulated karst pipeline 12; the sixth simulated karst pipeline 24 is parallel to the first simulated karst pipeline 20, and the seventh simulated karst pipeline 25 is parallel to the second simulated karst pipeline 19 and the third simulated karst pipeline 12; the third simulated karst pipeline 12 is connected to the water inlet pipe 9, and the seventh simulated karst pipeline 25 is connected to the drain pipe 26; the second simulated karst pipeline 19, the third simulated karst pipeline 12 and the fourth simulated karst pipeline 15 are each provided with a valve 7; the fifth simulated karst pipeline 16 is provided with two valves 7, and the two valves 7 are respectively provided near the connection with the second simulated karst pipeline 19 and the connection with the third simulated karst pipeline 12;

[0034] The groundwater parameter monitoring system 5 includes a groundwater level monitoring device, a groundwater flow rate monitoring device, a groundwater turbidity monitoring device and a groundwater chemical monitoring device, and the probes of each monitoring device are respectively placed at the pre-set measurement positions in the karst pipeline simulation system;

[0035] The groundwater parameter monitoring system 5 includes two sets of groundwater level monitoring devices, two sets of groundwater flow rate monitoring devices, and one set of groundwater turbidity monitoring devices and groundwater chemical monitoring devices, wherein the probe 10 of the groundwater level monitoring device and the probe 11 of the groundwater flow rate monitoring device are both arranged in the third simulated karst pipeline 12, and the probe 10 of the groundwater level monitoring device and the probe 11 of the groundwater flow rate monitoring device are arranged in the seventh simulated karst pipeline 25; the probe 17 of the groundwater turbidity monitoring device and the probe 13 of the groundwater chemical monitoring device are arranged in the fifth simulated karst pipeline 16;

[0036] The soil deformation monitoring system comprises three optical fibers 22 arranged in the original soil sample 23 in the soil box 3 and an optical fiber strain monitoring device 6 for monitoring the strain of the optical fibers 22 .

[0037] In the above embodiment, the groundwater level monitoring device adopts the 3001 Edge water level recorder of Canada's Solinst Company, the groundwater flow rate monitoring device adopts the 600 acoustic Doppler flow meter of the United States Flowstar Company, the groundwater turbidity monitoring device adopts the Turb2000 online turbidity analyzer of Germany's WTW Company, the groundwater chemical monitoring device adopts the MS6100 multi-parameter water quality online analyzer of the United States HACH Company, and the optical fiber strain monitoring device 6 adopts the BOTDR optical fiber strain tester of Japan's Ando Company.

[0038] In order to facilitate test observation, except for the main frame 18 made of metal material (such as stainless steel), other structures such as the box and the karst pipeline simulation system are preferably made of transparent materials. Each connection part in the device of the present invention needs to be checked for airtightness and liquid tightness.

[0039] The specific operation of using the system of the present invention is as follows:

[0040] 1) Before the test, first obtain the original soil of the field subsidence area, or reshape the soil according to the proportion of the subsidence area to make an original soil sample 23, put the original soil sample 23 into the soil box 3 according to the existing conventional rules, and at the same time bury optical fibers 22 for monitoring soil deformation and damage at different positions of the soil.

[0041] 2) Then, water is injected into the water inlet tank 4 in stages until the water level in the drainage tank 1 is in equilibrium with the water level in the drainage tank 1, simulating the actual Quaternary groundwater level in the field. The probes of each monitoring device are placed in the preset positions, and then water is injected into the water inlet pipe 9, so that the groundwater level in the drainage pipe 26 is in equilibrium with the water level in the water inlet pipe 9, simulating the karst groundwater under natural conditions.

[0042] 3) During the test, the switch and flow rate of each branch drainage pipe 27 on the drainage pipe 26 are controlled to simulate the water gushing or pumping process, and the readings of each monitoring instrument are obtained in real time until the soil is deformed and damaged to form a soil hole and collapse.

[0043] 4) Finally, by analyzing the corresponding relationship between the indicator parameters obtained from each monitoring and the soil deformation and failure stage, the comprehensive early warning threshold of multi-parameter monitoring of karst collapse is obtained to achieve early warning and forecast of karst collapse.

Claims

1. A karst collapse multi-parameter monitoring and early warning test system, comprising a karst collapse simulation system, a groundwater parameter monitoring system (5) and a soil deformation monitoring system, characterized in that: The karst collapse simulation system comprises a box and a karst pipeline simulation system, wherein: Two permeable baffles (2) are arranged in the box body, dividing the box body into three parts: a water inlet box (4), a soil box (3) and a drainage box (1), wherein the soil box (3) is located between the water inlet box (4) and the drainage box (1), and the water inlet box (4), the soil box (3) and the drainage box (1) achieve mutual circulation of liquids through the permeable holes on the permeable baffles (2); the soil box (3) is used to fill the original soil sample (23), and a through hole (21) is provided on the bottom end surface of the soil box (3); The karst pipeline simulation system is established according to actual conditions of exploration or karst collapse examples, and comprises a simulated cave (14), a first simulated karst pipeline (20), a second simulated karst pipeline (19), a third simulated karst pipeline (12) and a fourth simulated karst pipeline (15) connected to the simulated cave (14), a sixth simulated karst pipeline (24) connected to the second simulated karst pipeline (19), and a seventh simulated karst pipeline (25) connected to the second simulated karst pipeline (19), as well as an inlet pipe (9) and a drain pipe (26) for providing inlet and outlet of the simulated karst pipeline, a valve (7) and a pressure gauge (8) are provided on the inlet pipe (9) and the drain pipe (26), and a valve (7) is provided on each simulated karst pipeline as required to control the on and off of water flow; wherein, The first simulated karst pipeline (20) is in communication with a through hole (21) on the bottom end surface of the soil box (3); the second simulated karst pipeline (19) and the third simulated karst pipeline (12) are at the same horizontal position as the simulated cave (14); The second simulated karst pipeline (19), the third simulated karst pipeline (12) and the fourth simulated karst pipeline (15) form a loop through a fifth simulated karst pipeline (16), and the fifth simulated karst pipeline (16) is located below the second simulated karst pipeline (19) and the third simulated karst pipeline (12); The sixth simulated karst pipeline (24) is parallel to the first simulated karst pipeline (20), and the seventh simulated karst pipeline (25) is parallel to the second simulated karst pipeline (19) and the third simulated karst pipeline (12); The third simulated karst pipeline (12) is connected to the water inlet pipe (9), and the seventh simulated karst pipeline (25) is connected to the drainage pipe (26); The groundwater parameter monitoring system (5) comprises two sets of groundwater level monitoring devices, two sets of groundwater flow rate monitoring devices, one set of groundwater turbidity monitoring devices and one set of groundwater chemical monitoring devices, wherein the probe (10) of the groundwater level monitoring device and the probe (11) of the groundwater flow rate monitoring device are arranged in the third simulated karst pipeline (12), the probe (10) of the groundwater level monitoring device and the probe (11) of the groundwater flow rate monitoring device are arranged in the seventh simulated karst pipeline (25), and the probe (17) of the groundwater turbidity monitoring device and the probe (13) of the groundwater chemical monitoring device are arranged in the fifth simulated karst pipeline (16); The soil deformation monitoring system comprises an optical fiber (22) arranged in an original soil sample (23) in a soil box (3) and an optical fiber strain monitoring device (6) for monitoring the strain of the optical fiber (22).

2. The karst collapse multi-parameter monitoring and early warning test system according to claim 1 is characterized by: The number of the optical fibers (22) is set according to needs, and they are respectively buried in original soil samples (23) at different depths in the soil box (3).

3. The karst collapse multi-parameter monitoring and early warning test system according to claim 1 is characterized by: The drainage pipe (26) is arranged longitudinally, and a plurality of branch drainage pipes (27) are arranged on it, and each branch drainage pipe (27) is provided with a valve (7) and a pressure gauge (8).

Images