CN210834489U - Simulation experiment device for similar materials in water inrush process of bottom plate - Google Patents
Simulation experiment device for similar materials in water inrush process of bottom plate Download PDFInfo
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- CN210834489U CN210834489U CN201822021849.3U CN201822021849U CN210834489U CN 210834489 U CN210834489 U CN 210834489U CN 201822021849 U CN201822021849 U CN 201822021849U CN 210834489 U CN210834489 U CN 210834489U
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Abstract
The utility model discloses a bottom plate gushing water process similar material simulation experiment device relates to coal seam bottom plate gushing water technical field, include: the two-dimensional similar material simulation experiment table is fixed through four lateral supports, and each lateral support is fixed with a concrete foundation; the overlying load applying part comprises a plurality of round steel, and each round steel is welded with a handle; the aquifer simulation part comprises a water tank and an aggregate simulation aquifer, and the bottom of one side of the water tank is provided with a water inlet and a water outlet; the water pressure automatic control loading part comprises a valve A, a valve B, a water drain valve A, a check valve, a pressure regulating valve A and a valve E which are sequentially arranged on a main pipeline. The beneficial effects of the utility model are that, can effectively simulate bottom plate gushing water process and water guide channel development process to can accomplish the many first information data monitoring of gushing water in-process.
Description
Technical Field
The utility model relates to a coal seam bottom plate gushes water technical field, especially relates to a bottom plate gushes water process similar material simulation experiment device.
Background
In the serious disaster accidents of coal mines, the water damage accidents are only second to gas accidents, particularly the water inrush accidents of the bottom plate of a deep coal seam are increased, and the safe and efficient mining of deep coal resources is seriously influenced.
The water inrush process of the coal seam floor is explained by the scholars as follows: the coal seam bottom plate water inrush is the result of the combined action of mining mine pressure and bottom plate confined water pressure, mining mine pressure causes a water-conducting broken crack with a certain depth to appear on the water-resisting layer of the bottom plate, thereby reducing the strength of the rock mass, weakening the water-resisting performance, redistributing the bottom plate seepage field, and when confined water continuously seeps along the water-conducting broken crack, the rock mass is softened by seepage so as to cause the water-conducting broken crack to continue to expand upwards until the minimum main stress of the rock mass of the water-resisting layer of the bottom plate is smaller than the water pressure of the confined water by the interaction of the mining mine pressure and the bottom plate confined water pressure, so that the fracturing expansion is generated, and. It is also believed by the scholars that there are two basic ideas underlying the mechanism of water inrush: firstly, an inherent water-rich strong-seepage channel communicated with a water source exists in a bottom plate hydrogeological structure, and when the inherent water-rich strong-seepage channel is penetrated in the excavation process, a large amount of sudden water inrush is possibly generated to form water inrush disasters; secondly, the strong seepage channel does not exist in the bottom plate, but under the combined action of engineering stress, crustal stress, underground water and the like, the rock mass structure of the bottom plate and the inherent hydrogeological weak zone deform, disintegrate and destroy, so that a new penetrating strong seepage channel is formed, and water inrush is caused.
The water filling hydrogeological conditions of deep mines are increasingly complex, water inrush influencing factors are increased, water inrush accidents of a plurality of coal seam floor plates are not only related to two factors of water pressure and thickness in water inrush coefficients, and the water inrush mechanism and type are complex and changeable. Under the conditions of high stress-high confined water and original construction environment, the relation between water pressure and rock mass fracture expansion needs to be considered, and the constructions of fractures, karst collapse columns and the like existing in rock stratums need to be considered. Practice shows that the face appears in the coal seam mining process, so that the stress of the coal seam floor is redistributed, the initiation and the expansion of new cracks are further caused, the cracks gradually expand and extend to be mutually overlapped and communicated, and the cracks are further caused to expand to the face of the goaf, namely, the formation of the floor water bursting channel is caused by crack expansion, and the crack communication is used as a breakthrough.
SUMMERY OF THE UTILITY MODEL
In order to solve the technical problem, the utility model discloses a similar material simulation experiment device of bottom plate gushing water process.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
the utility model provides a similar material simulation experiment device of bottom plate gushing water process, includes two-dimentional similar material simulation experiment platform, coats that load applys part, aquifer simulation part and water pressure automatic control loading part, wherein:
the two-dimensional similar material simulation experiment table is characterized in that four corners of the experiment table are fixed through four lateral supports, a plurality of groups of screw holes for mounting protective channel steel and toughened glass are uniformly distributed on two stand columns of the experiment table, a first steel plate is further mounted between the two lateral supports positioned on the same side of the experiment table, and each lateral support is fixed with a concrete foundation;
the overlying load applying part comprises a plurality of round steel, each round steel is welded with a handle, and a second steel plate is inserted into the handles and is arranged on the protection channel steel;
the aquifer simulation part comprises a water tank and an aggregate simulation aquifer, wherein a water inlet and a water outlet are formed in the bottom of one side of the water tank, and the water inlet is connected with a main pipeline of the water pressure automatic control loading part;
the water pressure automatic control loading part comprises a valve A, a valve B, a water drain valve A, a check valve, a pressure regulating valve A and a valve E which are sequentially arranged on a main pipeline, a valve C is further arranged on a first branch pipeline between the valve A and the valve B, the first branch pipeline is connected to a booster pump, an automatic pressure controller is arranged on the booster pump, the booster pump is further connected with a second branch pipeline, and the second branch pipeline is connected to the main pipeline between the valve B and the water drain valve.
Furthermore, the lateral supports comprise support channel steel and inclined supports, one end of the support channel steel is fixedly connected with the test bed, and the other end of the support channel steel is fixed with the concrete foundation through two chemical expansion bolts; one end of the inclined support is fixedly connected with the upright post, and the other end of the inclined support is connected with the support channel steel.
Furthermore, three sides of the first steel plate are fixedly connected with the test bed and the two inclined supports respectively.
Further, the number of screw holes arranged on the upright post is 8 groups of 16, and the distance between two screw holes in each group is 10 cm.
Further, the handle in the overlying load application portion is made by bending a reinforcing bar.
Further, the water outlet in the aquifer simulation part is connected with a drainage system outside the experimental device.
Furthermore, in the water pressure automatic control loading part, a pressure gauge A is also arranged on a pipeline in front of the valve A, and a pressure gauge B and a flow gauge A are arranged on a pipeline behind the pressure regulating valve A.
Further, a valve D is also installed on the second branch line in the automatic water pressure control loading portion.
The beneficial effects of the utility model are that, according to the high confined water of deep mining, the new mechanics characteristic that plateau rock stress and strong disturbance and deep rock mass demonstrate, propose bottom plate gushing water process similar material simulation experimental apparatus, high durability and convenient operation, the experimental apparatus of preparation can effectively simulate "bottom plate stress redistribution → bottom plate water barrier deformation → crack extension → rock mass rupture → gushing water passageway forms → initiation bottom plate gushing water" gushing water process ization, the application indoor test is adopted the condition that the bottom plate gushing water process is studied and can realize the many first information monitoring of gushing water in-process under the condition, have important meaning to studying deep well bottom plate gushing water mechanism and water damage prediction forecast.
Drawings
Fig. 1 is a perspective view of a two-dimensional similar material simulation experiment table in the utility model;
FIG. 2 is a front view of a two-dimensional simulation experiment table for similar materials in the present invention;
fig. 3 is a side view of a two-dimensional similar material simulation experiment table in the present invention;
fig. 4 is a top view of a two-dimensional similar material simulation experiment table in the present invention;
FIG. 5 is a schematic view of an overlying load applying portion of the present invention;
fig. 6 is a schematic position diagram of an aquifer simulation part in the present invention;
fig. 7 is a schematic structural view of a simulated part of an aquifer in the utility model;
fig. 8 is a schematic view of the hydraulic automatic control loading part of the present invention.
Wherein, 1, a test bed; 2. laterally supporting; 3. protecting channel steel; 4. a chemical expansion bolt; 5. a first steel plate; 6. a screw; 7. a screw hole; 8. round steel; 9. a handle; 10. a second steel plate; 11. a water tank; 12. aggregate simulating an aquifer; 13. a water inlet; 14. a water discharge outlet; 15. a valve A; 16. a valve B; 17. a water drain valve A; 18. a check valve; 19. a pressure regulating valve A; 20. a valve E; 21. a booster pump; 22. an automatic pressure controller; 23. a pressure gauge A; 24. a valve C; 25. a valve D; 26. a pressure gauge B; 27. flow meter a.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The utility model provides a similar material simulation experiment device of bottom plate gushing water process, includes two-dimentional similar material simulation experiment platform, coats that load applys part, aquifer simulation part and water pressure automatic control loading part, wherein:
a two-dimensional similar material simulation experiment table, as shown in fig. 1-4, four corners of a test table 1 are fixed through four lateral supports 2, multiple groups of screw holes 7 for installing protective channel steel 3 and toughened glass are uniformly arranged on two upright posts of the test table 1, a first steel plate 5 is further arranged between the two lateral supports 2 positioned on the same side of the test table 1, each lateral support 2 is fixed with a concrete foundation, each lateral support 2 comprises a support channel steel and an inclined support, one end of the support channel steel is fixedly connected with the test table 1, and the other end of the support channel steel is fixed with the concrete foundation through two chemical expansion bolts 4; one end of each inclined support is fixedly connected with the upright post, the other end of each inclined support is connected with the support channel steel, and three side surfaces of the first steel plate 5 are respectively and fixedly connected with the test bed 1 and the two inclined supports; the number of the screw holes 7 arranged on the upright posts is 8 groups of 16, and the distance between two screw holes 7 in each group is 10cm, so that the protection channel steel 3 on two sides and the high-strength toughened glass can be conveniently installed.
The experiment table is made of Q235 hot-dip galvanized steel, the length of the experiment table is ×, the height of the experiment table is ×, the width of the experiment table is 2.6M × 2.1.1M × 0.2.2M, the chemical expansion bolts are 4M14 × 180, the first steel plate 5 is connected with the experiment table 1 and the two inclined supports through M14 screws 6, the effect of fixing the experiment table and transferring force is achieved, and the length of the supporting channel steel is 1.0M.
An overlying load applying part, shown in fig. 5, comprises a plurality of round steel 8, each round steel 8 is welded with a handle 9, each handle 9 is made of bent steel bars and is convenient to install and disassemble, the height of each round steel 8 is 125mm, the diameter of each round steel 8 is 160mm, the weight of each round steel 8 is 20Kg, and the number of the round steel 8 to be placed above the model can be converted according to the overlying load and the similarity ratio; second steel sheet 10 inserts in handle 9 and places in protection channel-section steel 3 on, the long 400mm of second steel sheet 10, thick 10mm, wide 60mm, if the model accident collapses, can effectively make somebody a mere figurehead round steel 8 on both sides protection channel-section steel 3, avoid the model to collapse and lead to round steel 8 to drop and injure the experimenter by a crashing object.
The aquifer simulation part comprises a water tank 11 and an aggregate simulation aquifer 12, the size of the stainless steel water tank 11 is 2.4m × 0.2.2 m × 0.2.2 m, a water inlet 13 and a water outlet 14 are arranged at the bottom of one side of the water tank 11, the water inlet 13 is connected with a main pipeline of the hydraulic pressure automatic control loading part, the water outlet 14 is connected with a drainage system outside an experimental device, in the actual operation process, stones and sands with different grain sizes are filled in the water tank 11, a coal seam floor aquifer rock stratum is simulated, and gaps among the aggregates simulate pores, cracks and karst caves in the coal seam floor aquifer.
The hydraulic pressure automatic control loading part comprises a valve A15, a valve B16, a water drain valve A17, a check valve 18, a pressure regulating valve A19 and a valve E20 which are sequentially arranged on a main pipeline, a valve C24 is further arranged on a first branch pipeline between the valve A15 and the valve B16, the first branch pipeline is connected to the booster pump 21, the booster pump 21 on-off pressure controller can realize the automatic opening and closing of the booster pump 21, if the pressure in the system reaches a preset value, the booster pump 21 is closed, and meanwhile, the check valve 18 plays a role in pressure stabilization; the booster pump 21 is provided with an automatic pressure controller 22, the booster pump 21 is also connected with a second branch pipeline, and the second branch pipeline is connected to a main pipeline between a valve B16 and a water drain valve; a pressure gauge A23 is further arranged on the pipeline in front of the valve A15, and a pressure gauge B26 and a flow gauge A27 are arranged on the pipeline behind the pressure regulating valve A19; a valve D25 is also mounted in the second branch line.
(5) The multivariate information data monitoring system part adopts the existing DH3816N data acquisition system, the stress sensor adopts a miniature soil pressure cell, the water pressure sensor adopts a miniature water pressure cell, when the batching is filled in the experiment table, according to the experimental scheme, the miniature soil pressure cell and the miniature water pressure cell end of the sensor are embedded in the experiment device, and the other end of the sensor is connected on the DH3816N data acquisition system to realize data monitoring.
A simulation experiment method for similar materials in a water inrush process of a bottom plate adopts the experiment device, and the simulation experiment process comprises the following steps:
(1) building two-dimensional similar material simulation experiment table
The lateral supports 2 fix four corners of the test bed 1, the test bed 1 is fixed on a concrete foundation by chemical expansion bolts 4, and the first steel plate 5 is fixedly connected with the test bed 1 and the two inclined supports through screws 6;
(2) determining an overburden load applying portion
According to the overlying load and the similarity ratio, the number of the round steel 8 to be placed above the device can be converted, a handle 9 is welded on each round steel 8, and a second steel plate 10 is inserted into each handle 9 and placed on the protection channel steel 3;
(3) making an aquifer simulation part
Adopting a stainless steel water tank 11 and an aggregate simulation aquifer 12, wherein a water inlet 13 and a water outlet 14 are reserved at the lower part of one side of the water tank 11, the water inlet 13 is connected with a water pressure automatic control loading system, the water outlet 14 is connected with a drainage system outside an experimental device, the water tank 11 is firstly placed on an experimental bench, the water tank 11 and two sides of the experimental bench are filled with rubber mats, the water tank 11 and a two-dimensional similar material simulation experimental bench are sealed by adopting a polyurethane foaming agent, after the water tank 11 is filled with aggregates, the water outlet 14 is closed, and then a water inlet pipe in a water pressure automatic control loading part is connected with the water inlet 13;
(4) arranging a hydraulic automatic control loading part
A valve A15, a valve B16, a water drain valve A17, a check valve 18, a pressure regulating valve A19 and a valve E20 are sequentially arranged on a main pipeline, an installation interface is 4 branch pipes, a valve C24 is installed on a first branch pipeline, the first branch pipeline is connected to a booster pump 21 provided with an automatic pressure controller 22, a second branch pipeline is communicated with the main pipeline, one end of the main pipeline is connected with external water supply, and the end provided with a valve E20 is connected with a water inlet 13 in the aquifer simulation part.
The automatic water pressure control process comprises the following steps:
(1) before excavation, closing the valve A15, observing the water pressure value of a pressure gauge A23, and if the water pressure value is more than or equal to the water pressure value required in the experimental device, closing the valve C24 and the valve D25 without opening the automatic pressurization system; if the water pressure is lower than the water pressure required in the experimental device, the valve B16 is closed, the valve C24 and the valve D25 are opened, and the automatic pressurization system is started.
(2) When the water supply pressure is greater than or equal to the water pressure value required in the experimental device, the water pressure loading process is as follows: opening the valve A15 and the valve B16, closing the water drain valve A17, opening the valve E20, and adjusting the pressure regulating valve A19 until the water pressure value of the pressure gauge B26 meets the design requirement of the model.
(3) When the water supply pressure is less than the water pressure value required in the experimental device, the water pressure loading process is as follows: opening a valve C24 and a valve D25, closing a valve B16, closing a water drain valve A17, opening a valve E20, and adjusting a pressure regulating valve A19 until the water pressure value of a pressure gauge B26 meets the design requirement of a model; when the water pressure is stabilized and the automatic pressure controller 22 reaches a design value, the booster pump 21 is closed, the check valve 18 prevents the water in the main line from flowing backward, and when the pressure is lowered, the automatic pressure controller 22 is activated and the booster pump 21 is opened to re-pressurize.
(4) When the pressure value is adjusted, the pressure-resistant hose connected with the valve E20 is connected with the water inlet 13 in the experimental device.
When the model is excavated, 5cm is excavated every time, 6 times of excavation are carried out every day, the top bottom plate rock stratum is continuously deformed and damaged in the excavation process, the confined water is continuously led and raised, the data acquisition system automatically acquires the stress and water pressure value in the water inrush process for the analysis and treatment of experimenters, and a certain theoretical basis is provided for monitoring and early warning of water inrush of the bottom plate of the deep well.
Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and the changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also belong to the protection scope of the present invention.
Claims (8)
1. The utility model provides a similar material simulation experiment device of bottom plate water inrush process, its characterized in that includes two-dimentional similar material simulation experiment platform, coats that the load applys part, aquifer simulation part and water pressure automatic control loading part, wherein:
the two-dimensional similar material simulation experiment table is characterized in that four corners of the experiment table are fixed through four lateral supports, a plurality of groups of screw holes for mounting protective channel steel and toughened glass are uniformly distributed on two stand columns of the experiment table, a first steel plate is further mounted between the two lateral supports positioned on the same side of the experiment table, and each lateral support is fixed with a concrete foundation;
the overlying load applying part comprises a plurality of round steel, each round steel is welded with a handle, and a second steel plate is inserted into the handles and is arranged on the protection channel steel;
the aquifer simulation part comprises a water tank and an aggregate simulation aquifer, wherein a water inlet and a water outlet are formed in the bottom of one side of the water tank, and the water inlet is connected with a main pipeline of the water pressure automatic control loading part;
the water pressure automatic control loading part comprises a valve A, a valve B, a water drain valve A, a check valve, a pressure regulating valve A and a valve E which are sequentially arranged on a main pipeline, a valve C is further arranged on a first branch pipeline between the valve A and the valve B, the first branch pipeline is connected to a booster pump, an automatic pressure controller is arranged on the booster pump, the booster pump is further connected with a second branch pipeline, and the second branch pipeline is connected to the main pipeline between the valve B and the water drain valve.
2. The simulation experiment device for the similar materials in the water inrush process of the bottom plate as claimed in claim 1, wherein the lateral supports comprise support channel steel and inclined supports, one end of the support channel steel is fixedly connected with the test bed, and the other end of the support channel steel is fixed with the concrete foundation through two chemical expansion bolts; one end of the inclined support is fixedly connected with the upright post, and the other end of the inclined support is connected with the support channel steel.
3. The simulation experiment device for the similar materials in the water inrush process of the bottom plate as claimed in claim 2, wherein three side surfaces of the first steel plate are fixedly connected with the test bed and the two inclined supports respectively.
4. The simulation experiment device for the similar materials in the water inrush process of the bottom plate as claimed in claim 1, wherein the number of the screw holes formed in the upright is 8 groups of 16, and the distance between two screw holes in each group is 10 cm.
5. The simulation experiment device for the similar materials in the water inrush process of the base plate as claimed in claim 1, wherein the handle in the upper load application part is formed by bending a steel bar.
6. The simulation experiment device for the base plate water inrush process similar material as claimed in claim 1, wherein the water outlet in the aquifer simulation part is connected with a drainage system outside the experiment device.
7. The simulation experiment device for the similar materials in the water inrush process of the soleplate as claimed in claim 1, wherein in the automatic water pressure control loading part, a pressure gauge A is further arranged on a pipeline in front of the valve A, and a pressure gauge B and a flow gauge A are arranged on a pipeline behind the pressure regulating valve A.
8. The simulation experiment apparatus for simulating a bottom plate water inrush process on a material according to claim 7, wherein a valve D is further installed on the second branch line in the hydraulic pressure automatic control loading part.
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| CN201822021849.3U CN210834489U (en) | 2018-12-04 | 2018-12-04 | Simulation experiment device for similar materials in water inrush process of bottom plate |
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| CN201822021849.3U CN210834489U (en) | 2018-12-04 | 2018-12-04 | Simulation experiment device for similar materials in water inrush process of bottom plate |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109406292A (en) * | 2018-12-04 | 2019-03-01 | 滨州学院 | A kind of Water Inrush process similar material simulation experiment device and method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109406292A (en) * | 2018-12-04 | 2019-03-01 | 滨州学院 | A kind of Water Inrush process similar material simulation experiment device and method |
| CN109406292B (en) * | 2018-12-04 | 2023-12-22 | 滨州学院 | Simulation experiment device and method for similar materials in water inrush process of bottom plate |
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