CN108205057B - Simulation test device for urban stratum collapse caused by water cut-off circulation path of underground engineering - Google Patents
Simulation test device for urban stratum collapse caused by water cut-off circulation path of underground engineering Download PDFInfo
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Abstract
The invention discloses a simulation test device for urban stratum collapse caused by water interception and circulation paths in underground engineering, and belongs to the technical field of ground collapse test devices. The device comprises an underground water level control structure, a model box (a water tank 1, a soil box and a water tank 2) for simulating ground collapse, a circulating water tank, a water circulation adjusting structure (a ground iron plate and a foundation pit plate), a screening channel and an underground water level control structure. The process that the stratum gradually expands from a small hole to a large hole under the action of water seepage due to the existence of the easily soluble filling material or the horizontal remodeling stratum in the simulated stratum, and the overlying soil layer becomes thin continuously and finally the stratum collapses. The invention mainly considers the influence of water circulation on soil cave expansion and the influence of soil cave development to critical burial depth to cut off water circulation on stratum collapse under the condition of horizontal seepage. The method can directly observe the process of soil cave expansion and collapse, and is used for researching the stratum collapse mechanism caused by the underground engineering water shut-off circulation path.
Description
Technical Field
The invention relates to a simulation test device and a critical soil cave simulation method for simulating urban stratum collapse caused by a cut-off water circulation path of underground engineering, and belongs to the technical field of ground collapse test devices.
Background
The physical model test is an important means for researching the safety prevention and control problem of the urban underground space, is widely applied at home and abroad, and plays an important role in engineering research and design. Scholars at home and abroad carry out highly effective research work aiming at the problem of ground collapse caused by urban subway tunnel excavation and foundation pit construction, and develop model test equipment with different scales and purposes.
At present, with the rapid development of urban construction in China, urban ground collapse accidents frequently occur, water circulation and soil holes in the land objectively exist, a plurality of buildings are destroyed and rebuilt at present, some building materials such as gypsum, calcium carbonate and the like are directly buried under the ground to form a layer of horizontally soluble stratum with uneven thickness, and due to the seepage effect of water in the soil, the building materials are gradually dissolved in water to form holes in the soil, under the action of horizontal seepage, the holes gradually develop and expand to enable the soil covering depth to be continuously thinned, the holes in the initial stage are not large, due to the existence of the soil arch effect, the ground collapse cannot be caused, but the holes continue to develop upwards, the thickness of covering soil becomes continuously thinner, finally the soil arch effect disappears, and the ground collapse occurs. In recent years, as ground collapse accidents increase year by year, related researches are in a primary stage, and the catastrophe mechanism and the evolution rule of the accidents cannot be fundamentally known, so that reasonable and effective preventive measures and prevention and treatment methods cannot be provided. This patent provides a test device, tries to simulate the level and remolds soil hydrologic cycle in the stratum and promotes the hole development, and final hole development reaches the critical state, and hydrologic cycle is cut off and is aroused the ground and cave in to know and solve above-mentioned problem.
The geometric similarity ratio of the physical model test is a key technical index, the geometric similarity ratio is too small, although test materials can be saved and the operation is convenient, the quantity of the too small model can limit the arrangement of soil caves and seepage paths, and meanwhile, the narrow operation space is easy to be interfered by external factors, so that the test precision is influenced. Therefore, under the condition permission, a larger geometric similarity ratio of the model is adopted as much as possible, which increases the difficulty of the model test process. For example, the material consumption of a large-size model box is large, and the soil material consumption, the size of a soil cave and the size of a seepage path are correspondingly increased when the actual working condition is simulated. With the development of underground spaces, ground collapse accidents are more and more, and a catastrophe mechanism and an evolution mechanism of the ground collapse caused by the fact that the soil water circulation is cut off are urgently needed to be fully known through a model test, so that a reliable basis is provided for collapse prediction and prevention.
Disclosure of Invention
The invention aims to provide a simulation test device for urban stratum collapse caused by cutting off water circulation paths in underground engineering so as to fully know the catastrophe mechanism and the evolution mechanism of urban ground collapse.
In order to achieve the purpose, the technical scheme of the patent is as follows:
a simulation test device for urban stratum collapse caused by water circulation interruption in underground engineering comprises a model water tank I1, a model soil tank 2, a model water tank II 3, a water circulation adjusting structure 4, an underground water level control structure 5, a screening channel 6 and a circulating water tank 7; the model water tank I1 and the model water tank II 3 are respectively positioned at the left side and the right side of the model soil box 2, and permeable membranes are arranged between the model water tank I1 and the model water tank II 3 and the model soil box 2; two cavities are formed in the model water tank I1 and the model water tank II 3 at intervals by the underground water level control structure 5; a screening channel 6 is arranged in a cavity of the model water tank II 3 close to the model soil tank 2; the circulating water tank 7 is communicated with a cavity, close to the model soil box 2, in the model water tank I1 through a first water inlet hose 7-7, and the circulating water tank 7 is communicated with a cavity, far away from the model soil box 2, in the model water tank I1 through a first water outlet hose 7-8; the circulating water tank 7 is communicated with a cavity in the model water tank II 3, close to the model soil box 2, through a second water inlet hose 7-9, and the circulating water tank 7 is communicated with a cavity in the model water tank II 3, far away from the model soil box 2, through a second water outlet hose 7-10; a water pipe switch 7-1 and a flowmeter 7-2 are respectively arranged on the first water inlet hose 7-7, the first water outlet hose 7-8, the second water inlet hose 7-9 and the second water outlet hose 7-10; the inside soil material that fills of model soil box 2, arrange seepage flow path and simulation soil cave in the soil material, screening 6 one end of passageway is inserted in the soil material in the model soil box 2 to the parcel seepage flow path, the other end is fixed with model water tank two 3 gomphosis, connects with steel sheet operation platform on the model water tank 1.
In a further improvement, the model water tank I1, the model soil box 2 and the model water tank II 3 are all made of organic glass.
In a further improvement, scales are arranged on an organic glass panel of the model soil box 2 and are uniform, the measuring range is 0.5m, the first section of the measuring range is 0.1m in millimeter as precision, and the back section of the measuring range is 0.4m in centimeter as precision.
The simulation of the seepage path adopts a random method to throw iron wires into the air, the simulation of the seepage path adopts soil and soluble substance mixed simulation, and the simulation of the initial soil hole in the soil is formed by adopting the simulation of a spherical mixture of salt and soil.
In a further improvement, the screening channel 6 in the model water tank II 3 is a transparent glass channel, wherein the glass channel is provided with four layers of screening cross sections, the screening cross sections are formed by iron wires, the four layers of screening cross sections divide the whole screening channel into 5 particle size spaces, and a geotextile bag is connected below each space.
The water circulation adjusting structure 4 comprises a permeable membrane, a groove 4-2, a fixed steel plate 4-3, a scale screw rod 4-6, a bearing 4-7, a screw cap 4-4, a torsion disc 4-5 and a simulation plate, wherein the torsion disc 4-5 is connected with one end of the screw rod 4-6, and the other end of the screw rod 4-6 is rotatably connected with the simulation plate through the bearing 4-7; the screw cap 4-4 is sleeved on the screw rod 4-6 in a threaded manner and is fixedly connected with the fixed steel plate 4-3.
In a further improvement, the simulation plate is a foundation pit excavation simulation plate 4-8 or a subway excavation simulation plate 4-9.
In a further improvement, the underground water level control structure 5 comprises a plurality of water level baffles 5-1, the water level baffles 5-1 are stably embedded at two sides of the model box, and the adjacent water level baffles 5-1 are stably embedded from top to bottom.
Further improvement, the water level baffle 5-1 is gradually shortened from bottom to top, and the length of the water level baffle 5-1 is 0.5m, 0.05m, 0.02m, 0.01m and 0.005m from large to small.
Specifically, the invention provides a simulation test device for urban stratum collapse caused by water circulation interruption in underground engineering, which comprises soil, a model water tank I1, a model soil tank 2, a model water tank II 3, a water circulation adjusting structure 4, an underground water level control structure 5, a screening channel 6 and a circulating water tank 7.
The circulating water tank 7 is provided with 4 inlets and outlets, namely a left water inlet 7-5), a left water outlet 7-6, a right water inlet 7-3 and a right water outlet A7-4. Wherein, the left water inlet and the water outlet at the bottom of the circulating water tank 7 control the supply of the left model water tank I1 and the supply of the right water inlet and the water outlet control model water tank II 3, and the left water inlet and the right water inlet in the water tank are connected with a water pump.
In order to avoid unstable water level in the underground water level control structure 5, the inner diameters of transparent steel wire pipes of the water inlet and the water outlet of the model water tank I1 and the model water tank II 3 are different in size, the diameter of the water inlet is larger than that of the water outlet, and stable water level in the model water tank I1 and the model water tank II 3 is guaranteed.
The invention provides a simulation test device for urban stratum collapse caused by water interception and circulation paths in underground engineering. The system can simulate the accidents of urban area ground subsidence caused by water circulation cutoff caused by foundation pit excavation and subway excavation, wherein the foundation pit excavation can simulate the accidents of road subsidence caused by adopting artificial precipitation modes such as well-point precipitation and the like, and simulate the expansion of soil caverns under the existence of soil water circulation in a horizontal solubility remolding stratum. The test device can realize the simulation of the actual working condition of ground collapse, can perform various physical model tests such as different soil conditions, soil caves at different positions, different seepage paths, water supply cutting, water drainage cutting, soil water circulation cutting and the like, can be used for the simulation test of ground collapse caused by water circulation cutting due to municipal project construction such as foundation pit excavation, subway construction and the like, and can realize the water circulation of the whole system.
In order to clearly see the development process of the holes in the soil, the device adopts a semi-structure mode, the soil body is subjected to layered dyeing, the displacement development condition of the soil body can be clearly and clearly seen through the transparent glass and is recorded through the high-pixel camera.
The invention can artificially control the height of the water level baffle 5-2 in the underground water level control structure 5 to control the height of the underground water level.
The water circulation baffle plates in the device are two, wherein one baffle plate A is 1m multiplied by 1m in size to simulate foundation pit excavation and cut off water circulation, and the other baffle plate B is 1m multiplied by 0.2m to simulate subway excavation and cut off water circulation. The shielding area of the baffle A is in direct proportion to the excavation depth of the foundation pit, while the shielding area of the baffle B is fixed and is positioned at the excavation position of the subway.
The invention can simulate the soil cave expansion caused by groundwater circulation and the stratum collapse of the critical buried deep soil cave caused by water circulation truncation or change according to various working conditions. The working conditions of underground water level change caused by various conditions and influence on water circulation so as to influence soil cavern expansion and collapse can be simulated.
Drawings
The drawings are only intended to illustrate and explain the present invention and do not limit the scope of the invention. Wherein,
FIG. 1 is a schematic perspective view of a test device for simulating underground works to change water flow paths to cause collapse of urban strata.
FIG. 2 is a top view of the mold box.
Figure 3 is a three view of the screening channel.
Fig. 4 is a side view of the model soil box.
Figure 5 is a schematic diagram of a screening card slot configuration.
Fig. 6 is a schematic view of the water level barrier.
Fig. 7 is a view showing a structure of a water circulation adjustment.
Fig. 8 is a vertical sectional view of the earth.
Fig. 9 is a horizontal sectional view of the earth material.
Fig. 10 is a schematic structural view of the circulation tank.
Description of reference numerals: 1 model water tank I, 1-1 ladder stand, 1-2 operation platform, 1-3 steel plate, 2 model soil box, 2-1 vertical displacement scale, 3 model water tank II, 3-1 first permeable membrane, 4 water circulation adjusting structure, 4-1 second permeable membrane, 4-2 groove, 4-3 fixed steel plate, 4-4 screw cap, 4-5 torsion disc, 4-6 scale screw, 4-7 bearing, 4-8 foundation pit excavation simulation board, 4-9 subway excavation simulation board, 5 underground water level control structure, 5-1 water level baffle, 6 screening channel, 6-1 screening clamping groove, 6-2 soil material inlet, 6-3 screening grid groove, 6-4 screening bag, 6-5 screening net, 7 circulation water tank, 7-1 water pipe switch, 7-2 flow meter, 7-3 right water inlet, 7-4 right water outlet, 7-5 left water inlet, and 7-6 left water outlet.
Detailed Description
For the purpose of clearly understanding the technical features, objects and effects of the present invention, embodiments of the present invention will now be described with reference to the accompanying drawings. Wherein like parts are given like reference numerals.
Fig. 1 is a schematic perspective view showing a simulation test apparatus for urban stratum collapse caused by water circulation interruption in underground works, which roughly shows the general structure of the simulation test apparatus for urban stratum collapse caused by water circulation interruption in underground works, and emphatically shows the feasibility of model box simulation of collapse caused by water circulation interruption and the influence of water circulation on the initial soil cave expansion. The dimensions of the mold box are 1m × 1m × 2m in length × width × height.
As shown in the figure, the simulation test device for urban stratum collapse caused by water interception and circulation paths of underground engineering integrally comprises soil, a model water tank I1, a model soil tank 2, a model water tank II 3, a water circulation adjusting structure 4, a circulation water tank 7, a screening channel 6 and an underground water level adjusting structure 5. The model water tank I1, the model soil tank 2, the model water tank II 3, the water circulation adjusting structure 4, the underground water level control structure 5, the soil cave simulation, the seepage path and the screening channel 6 are main structures of a simulation test device for causing urban stratum collapse due to water circulation interruption path of underground engineering, a water outlet of the model water tank II 3 is connected with a right water outlet of the circulation water tank 7, and a submersible pump placed in the circulation water tank is connected with the model water tank I and the model water tank II. Namely, the simulation test device for urban stratum collapse caused by the cut water circulation path of the underground engineering at least comprises a soil material filling model soil box 2 for simulating ground collapse, a model water box I1 and a model water box II 3 for controlling the underground water level, a water circulation adjusting structure 4, a soil cave simulation, a seepage path simulation and screening channel 6 and an underground water level control structure 5.
Wherein the model box is made of organic glass plates with the thickness of 5mm, and stiffening ribs are additionally arranged around the model box; the organic glass is connected through a clamping groove, the connection is as shown in figure 2, after the organic glass is placed into the clamping groove, the clamping groove is filled with glass cement, the connection is sufficient, a steel plate 1-3 is fixed on an organic glass plate of a first mold box 1, a ladder stand 1-1 is welded on the steel plate, a steel plate is placed at the top to serve as an operation platform 1-2, and the steel plate at the top is welded with the other two steel plates.
The model soil box 2 can be transported without connecting the model box, part of the soil is transported from the right side, then the model box is connected, layered compaction is carried out, and when the soil height reaches the seepage path and the soil hole height, the soil hole and the seepage path are buried.
The horizontal direction of a seepage path in the horizontal easily soluble remolded stratum under a natural condition is not clear, the seepage path has certain randomness, and in order to simulate the seepage path, a path which is roughly formed by throwing iron wires into the air and falling the iron wires onto the plane of a model box is adopted to simulate the seepage path in the easily soluble remolded stratum under the natural condition. After the path direction is determined, a toothpick or a slender rod-shaped object is used for digging a small groove in the model box along the direction of the iron wire, and a saline soil mixture which is already uniformly mixed is filled to simulate a seepage path. The percolation path will have 4 from top to bottom. Simulation of soil cave A hemispherical object was filled with a mixture of saline and soil on a model soil box as a simulated soil cave, and then gently compacted by covering with soil carefully, followed by transporting in the remaining soil. Firm in connection comes through bolt and glass cement between mold box and the mold box, and there is the reinforcing bar around the mold box to encircle the reinforcement, has 4 layers from last to having, and the reinforcing bar diameter is 1 cm.
Before a water pump in a circulating water tank is started, a water level baffle 5-1 in an underground water level adjusting structure of a model water tank I1 and a model water tank II 3 is combined to a required height in advance, a permeable membrane is placed between a model soil tank 2 and the model water tank I1 and the model water tank II 3 to enable a contact surface of soil and water to have an anti-seepage surface, a screening channel is inserted into soil to wrap a seepage path, the water level baffle is combined to a preset height, and then the water pump is started.
The screening channel is a transparent glass tube, the inside of the glass tube is divided into 5 particle size spaces by a screening grid formed by 4 layers of iron wire nets, and each particle size space is adjusted in size of the particle size of the space by adjusting the size of the screening grid. After water circulation begins, water flows into the screening channel from the seepage path, and finally the soil material finally falls into screening bags with different particle sizes through layer-by-layer screening, so that the seepage-carried soil material is screened.
The water circulation adjusting structure 4 is connected with a screw cap 4-4 fixed on a steel plate at the top of the model water tank, and the screw cap 4-4 is fixed, the water circulation adjusting structure 4 only rotates along the screw cap 4-4 to move up and down under the rotation of the torsion disc 4-5, and because the connection between the simulated baffle plate at the lower part of the water circulation adjusting structure 4 and the scale screw rod 4-6 is connected through the bearing 4-7, so the scale screw 4-6 and the simulation baffle can be twisted at will, but when the scale screw 4-6 moves up and down through the twisting disc 4-5, the simulation board in the water circulation adjusting structure 4 can also move up and down along with the scale screws 4-6, but the simulation board can not rotate, and the water circulation adjusting structure 4 is a stepless speed regulating structure, so that the vertical moving distance of the simulation board can be adjusted at will according to the requirement.
After water circulation begins, upward development speed of a hole is observed through scales of a model soil box, upward expansion displacement in unit time is recorded, when the thickness of the covering soil reaches critical burial depth, a steel plate operation platform of the model soil box I1 is climbed through a crawling ladder, a torsion disc is rotated so that a simulation board subway excavation simulation board or a foundation pit excavation simulation board is moved to a specified height, collapse conditions of the soil hole are observed, a screening channel is taken out from a model water box II, then automatically classified particle size in the screening channel is weighed, and a curve of upward expansion speed of the hole along with time change in particle-level soil distribution is recorded. And observing the change of the critical burial depth of the holes with different diameters under the condition that the water circulation is cut off.
The simulation test device for stratum collapse caused by the water shut-off circulation path of the underground engineering has the other remarkable characteristic that the structure size is larger, the size of the model box is 1m multiplied by 2m multiplied by width multiplied by height, and compared with a solid model, the model box with the size can truly reflect the problem of road surface collapse under the actual working condition.
The invention can simulate the influence of the change of the water circulation direction of the seepage path on the hole expansion under various working conditions, and can realize the adjustment of the underground water level adjusting system under the condition that the normal water level difference exists. The foundation ditch excavation can take modes such as well point precipitation sometimes to reduce the ground water level height around the foundation ditch to guarantee the construction, there is the research to show, when using well point precipitation, form a hourglass hopper-shaped ground water level easily on every side, if the soil cave is in funnel line below, then the hydrologic cycle in the seepage flow path through the soil cave can be reverse, this is called as the condition 1, if the soil cave is in funnel line top, then the hydrologic cycle in the seepage flow path through the soil cave can reverse the end, this is called as the condition 2. Therefore, when the simulated foundation pit adopts a mode of lowering the underground water level around the foundation pit like well point precipitation and the like, for the condition 1, the change of water seepage in soil near the peripheral pit caused by the excavation of the foundation pit can be realized by lowering the water circulation adjusting plate and lowering the water level height of the model water tank I1, and the water level height of the model water tank II 3 is ensured to be higher than the underground water level height of the model soil tank; for the condition 2, the simulation can be realized by reducing the water circulation adjusting plate and the water level height of the model water tank I1, the water level of the model water tank II 3 is higher than the underground water level height of the model soil tank I1, and if the foundation pit construction is guaranteed by adopting a waterproof curtain, the foundation pit construction can be guaranteed, and the water circulation adjusting plate can be reduced during the simulation, but the water level height of the model water tank I1 is not changed. For the simulation of tunnel excavation water circulation cut-off, the water circulation adjusting plate earth iron plate can be moved to the seepage path opening, so that the water circulation cut-off condition of tunnel excavation is simulated by cutting of water circulation.
In addition, for the full-structure underground model test, it becomes more difficult to conveniently observe the experimental phenomenon. The simulation test device for stratum collapse caused by water circulation interruption of underground engineering adopts the thought of a semi-structural model test, can not completely and truly reflect the actual working condition like a full-structural model test, but has a definite proportional relation with the full-structural model test result and consistent test phenomenon change rule, and can be used for researching ground collapse catastrophe mechanism and evolution rule caused by water circulation interruption of easily-reconstructed stratum surface soil.
The invention provides a test device for simulating surface subsidence caused by changing water flow path in underground engineering, which can be used for various physical model tests such as different soil conditions, different burial depths, water supply cutting, water drainage cutting, soil water circulation cutting and the like, can be used for a simulation test of surface subsidence caused by water circulation cutting in the using process after municipal road construction is finished, and has the size of a model box of 1m multiplied by 2m in length multiplied by width multiplied by height.
The cutting off of the water circulation is realized through a water circulation simulation plate, and a water circulation adjusting plate is lowered to a specified height on a steel plate operating platform 1-2 through a rotating screw cap according to needs.
The adjustment of the groundwater level height of the model box is realized by adjusting the height of a water level baffle 5-1 in the groundwater level control structure, and the water level heights at two sides can be adjusted as required.
Respectively carrying out water circulation tests with different percentages of the content of soluble substances in soil, recording seepage water quantity and seepage sand quantity of the same soil cave and the same seepage path before collapse, then carrying out the water circulation test with the same percentage of the content of saline soil, and recording seepage water quantity and seepage sand quantity of the different soil caves in the same seepage path before collapse. The pipe orifices of the water inlet and outlet pipes are provided with flow meters, the water level of the water tank is unchanged, and the water inlet and outlet amount of the soil box can be calculated.
The above description is illustrative of the present invention and is not intended to limit the scope of the present invention, and any person skilled in the art should understand that they can make equivalent changes, modifications and combinations without departing from the spirit and principle of the present invention.
Claims (8)
1. A simulation test device for urban stratum collapse caused by water circulation interruption in underground engineering is characterized by comprising a model water tank I (1), a model soil tank (2), a model water tank II (3), a water circulation adjusting structure (4), an underground water level control structure (5), a screening channel (6) and a circulation water tank (7); the model water tank I (1) and the model water tank II (3) are respectively positioned at the left side and the right side of the model soil box (2), and permeable membranes are arranged between the model water tank I (1) and the model water tank II (3) and the model soil box (2); two cavities are formed in the model water tank I (1) and the model water tank II (3) at intervals by the underground water level control structure (5); a screening channel (6) is arranged in a cavity of the model water tank II (3) close to the model soil tank (2); the circulating water tank (7) is communicated with a cavity, close to the model soil box (2), in the model water tank I (1) through a first water inlet hose (7-7), and the circulating water tank (7) is communicated with a cavity, far away from the model soil box (2), in the model water tank I (1) through a first water outlet hose (7-8); the circulating water tank (7) is communicated with a cavity, close to the model soil box (2), in the model water tank II (3) through a second water inlet hose (7-9), and the circulating water tank (7) is communicated with a cavity, far away from the model soil box (2), in the model water tank II (3) through a second water outlet hose (7-10); a water pipe switch (7-1) and a flowmeter (7-2) are respectively arranged on the first water inlet hose (7-7), the first water outlet hose (7-8), the second water inlet hose (7-9) and the second water outlet hose (7-10); soil is filled in the model soil box (2), a seepage path and a simulated soil cave are arranged in the soil, one end of a screening channel (6) is inserted into the soil in the model soil box (2) and wraps the seepage path, the other end of the screening channel is embedded and fixed with the model water tank II (3), and a steel plate operation platform is connected on the model water tank I (1);
the screening channel (6) in the model water tank II (3) is a transparent glass channel, wherein the glass channel is provided with four layers of screening cross sections, the screening cross sections are formed by iron wires, the four layers of screening cross sections divide the whole screening channel into 5 particle size spaces, and a geotextile bag is connected below each space.
2. The simulation test device for inducing urban stratum collapse by intercepting water circulation paths in underground works according to claim 1, characterized in that: the model water tank I (1), the model soil box (2) and the model water tank II (3) are all made of organic glass.
3. The simulation test device for inducing urban stratum collapse by intercepting water circulation paths in underground works according to claim 1, characterized in that: scales are arranged on an organic glass panel of the model soil box (2), the scales are uniform, the measuring range is 0.5m, the first section 0.1m of the measuring range takes millimeters as the precision, and the back section 0.4m of the measuring range takes centimeters as the precision.
4. The simulation test device for inducing urban stratum collapse by intercepting water circulation paths in underground works according to claim 1, characterized in that: the simulation of the seepage path adopts a random method to throw iron wires into the air, the simulation of the seepage path adopts the mixed simulation of soil and soluble substances, and the simulation of the initial soil hole in the soil is formed by the simulation of a spherical mixture of salt and soil.
5. The simulation test device for inducing urban stratum collapse by intercepting water circulation paths in underground works according to claim 1, characterized in that: the water circulation adjusting structure (4) comprises a permeable membrane, a groove (4-2), a fixed steel plate (4-3), a scale screw rod (4-6), a bearing (4-7), a screw cap (4-4), a torsion disc (4-5) and a simulation plate, wherein the torsion disc (4-5) is connected with one end of the screw rod (4-6), and the other end of the screw rod (4-6) is rotatably connected with the simulation plate through the bearing (4-7); the screw cap (4-4) is sleeved on the screw rod (4-6) in a threaded manner and is fixedly connected with the fixed steel plate (4-3).
6. The simulation test device for inducing urban stratum collapse by intercepting water circulation paths in underground works according to claim 5, is characterized in that: the simulation board is a foundation pit excavation simulation board (4-8) or a subway excavation simulation board (4-9).
7. The simulation test device for inducing urban stratum collapse by intercepting water circulation paths in underground works according to claim 1, characterized in that: the underground water level control structure (5) comprises a plurality of water level baffles (5-1), the water level baffles (5-1) are stably embedded at two sides of the model box, and the adjacent water level baffles (5-1) are stably embedded from top to bottom.
8. The simulation test device for urban area stratum collapse caused by intercepting water circulation paths in underground engineering according to claim 7, is characterized in that: the water level baffle (5-1) is gradually shortened from bottom to top, and the lengths of the water level baffle (5-1) are 0.5m, 0.05m, 0.02m, 0.01m and 0.005m from large to small.
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CN109507085B (en) * | 2018-12-29 | 2021-05-28 | 水利部交通运输部国家能源局南京水利科学研究院 | True triaxial experiment device and method for simulating multidirectional seepage of soil and stone materials |
CN111044704A (en) * | 2019-12-03 | 2020-04-21 | 南昌大学 | Pipeline dissolution test equipment and method based on soil body internal erosion |
CN113567317A (en) * | 2021-06-22 | 2021-10-29 | 济南轨道交通集团有限公司 | Testing device and system for underground water seepage simulation of subway structure |
CN114441406B (en) * | 2022-01-05 | 2023-04-07 | 中交第四航务工程局有限公司 | Test system and test method for simulating local seepage of waterproof curtain of foundation pit |
CN115184579B (en) * | 2022-06-20 | 2023-03-24 | 北京科技大学 | Device and method for testing disaster-causing evolution of cavity collapse hidden danger in whole process |
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CN105784562A (en) * | 2016-03-08 | 2016-07-20 | 同济大学 | Transparent soil test device used for simulating seepage of foundation pit dewatering confined aquifer underground water |
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CN105784562A (en) * | 2016-03-08 | 2016-07-20 | 同济大学 | Transparent soil test device used for simulating seepage of foundation pit dewatering confined aquifer underground water |
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