CN216524522U - Outer water pressure test equipment of rich water stratum tunnel lining - Google Patents
Outer water pressure test equipment of rich water stratum tunnel lining Download PDFInfo
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- CN216524522U CN216524522U CN202123020014.4U CN202123020014U CN216524522U CN 216524522 U CN216524522 U CN 216524522U CN 202123020014 U CN202123020014 U CN 202123020014U CN 216524522 U CN216524522 U CN 216524522U
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 204
- 238000012360 testing method Methods 0.000 title claims abstract description 84
- 239000002689 soil Substances 0.000 claims abstract description 35
- 239000011521 glass Substances 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 3
- 235000017166 Bambusa arundinacea Nutrition 0.000 claims 2
- 235000017491 Bambusa tulda Nutrition 0.000 claims 2
- 241001330002 Bambuseae Species 0.000 claims 2
- 235000015334 Phyllostachys viridis Nutrition 0.000 claims 2
- 239000011425 bamboo Substances 0.000 claims 2
- 239000011435 rock Substances 0.000 abstract description 11
- 238000010276 construction Methods 0.000 abstract description 4
- 238000013461 design Methods 0.000 abstract description 4
- 238000012423 maintenance Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 description 10
- 238000009933 burial Methods 0.000 description 6
- 230000003068 static effect Effects 0.000 description 6
- 229920006395 saturated elastomer Polymers 0.000 description 4
- 230000035699 permeability Effects 0.000 description 3
- 238000010998 test method Methods 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
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- 239000000463 material Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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Abstract
Outer water pressure test equipment of rich water stratum tunnel lining, its characterized in that: the tunnel lining model is arranged at the bottom of the cylindrical test box body; the outer side of the tunnel lining model is provided with a water pressure sensor, and one or more layers of simulated soil samples are buried in the test box body above the water pressure sensor; the test box body is formed by splicing a bottom box barrel with a bottom and a plurality of sections of box barrels without bottoms; a water inlet pipe with a valve is arranged at the top of the test box body; the bottom box barrel and the box barrel are both provided with drain pipes with valves, and the drain pipes are provided with flow velocity meters. The device can simulate the environments of different surrounding rocks, different water head heights and different drainage conditions of the water-rich stratum, and measure the external water pressure borne by the tunnel lining in a specific environment; the measured external water pressure value is closer to the water pressure value of the tunnel lining in the actual engineering, so that more accurate test basis can be provided for the water pressure resistant waterproof design, construction and maintenance of the water-rich stratum tunnel; and further, the safe operation of the tunnel is better ensured.
Description
Technical Field
The utility model relates to a test device for the external water pressure of a subway tunnel lining.
Background
When the subway tunnel passes through a water-rich stratum with high water pressure (high water head) such as a water bottom or a mountain with a reservoir, a lake and an underdrain, the original water system balance of the water-rich stratum is damaged by the tunnel, and the tunnel becomes a channel for collecting underground water near the water-rich stratum. The tunnel is communicated with the water-containing stratum, the tunnel lining (tunnel structure) is in a high water head (high water pressure) environment, the borne water pressure is very large, and the water damage of the tunnel is easy to occur. In order to avoid water damage and ensure the safe operation of the tunnel, measures must be taken to increase the water pressure resistance and the leakage resistance of the tunnel lining. For example, the water pressure resistance, permeability resistance and water resistance of concrete used for lining are improved; and (3) applying drainage facilities on the concrete lining: a blind ditch (pipe) is formed behind (on the periphery of) the lining, water enters the blind ditch from the cracks of the surrounding rocks, then enters a longitudinal drainage ditch in the tunnel through drainage holes penetrating through the side wall of the lining, and is discharged outwards, so that the water pressure born by the lining is reduced. These measures to enhance the water pressure resistance of the tunnel lining presuppose that the external water pressure to which the tunnel lining is subjected in a water-rich environment must be accurately known.
At present, the method for determining the external water pressure of the lining is generally to calculate and estimate by adopting an empirical formula according to the geological conditions of surrounding rocks obtained by geological exploration. The calculation estimated value of the empirical formula has larger deviation compared with the actual value of the lining in the actual engineering, which causes resource waste or water leakage of the lining. The outer water pressure that tunnel lining receives under specific soil sample, specific flood peak height and drainage measure need be surveyed through special test device in the experiment, for the waterproof design of water-rich stratum tunnel's water pressure resistance, construction and maintenance, provide more accurate experimental basis.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a test device for the external water pressure of the tunnel lining of the water-rich stratum, which can simulate the environments of different surrounding rocks, different water head heights and different drainage conditions of the water-rich stratum so as to measure the external water pressure borne by the tunnel lining in a specific environment; the measured external water pressure value is closer to the water pressure value of the tunnel lining in the actual engineering, so that more accurate test basis can be provided for the water pressure resistant waterproof design, construction and maintenance of the water-rich stratum tunnel; and further, the safe operation of the tunnel is better ensured.
The technical scheme adopted for realizing the purpose of the utility model is that the external water pressure test equipment for the water-rich stratum tunnel lining comprises a test box body and a tunnel lining model in the test box body, and is characterized in that:
the tunnel lining model is arranged at the bottom of the cylindrical test box body, more than four water pressure sensors are arranged on the outer side of the tunnel lining model, and output lines of the water pressure sensors penetrate through the test box body to be connected with the signal acquisition and analysis system; one or more layers of simulated soil samples are embedded in the test box body above the tunnel lining model;
the cylindrical test box body is formed by splicing a bottom box barrel with a bottom and a plurality of sections of box barrels without bottoms; the top of the test box body is provided with a water inlet pipe with a valve; the bottom box cylinder and the box cylinder are both provided with drain pipes with valves, and flow velocity meters are installed on the drain pipes.
One operation step and working process for testing the external water pressure of the tunnel lining of the water-rich stratum by using the testing equipment is as follows:
A. filling and compacting one or more layers of simulated soil samples into the test box body to enable the total height of the simulated soil samples to reach a set height;
B. opening a valve of the water inlet pipe, and injecting water into the test box body until the simulated soil sample is saturated, wherein the water level is higher than or equal to the height of the simulated soil sample, and the water level is stabilized to a set height; closing the valve of the water inlet pipe; the signal acquisition and analysis system acquires and processes the signal of the water pressure sensor at the moment to obtain the external water pressure value of the tunnel lining;
C. changing different simulated soil samples and the heights of the simulated soil samples layer by layer and changing the set height of the water level; and (6) repeating the operation of the step A, B to obtain the outer water pressure values of the tunnel lining of the water-rich stratum under different surrounding rock types, different lining burial depths and different water heads.
The technical scheme is suitable for the external water pressure test of the tunnel lining of the water-rich stratum without taking a drainage measure.
The other operation steps and working process of testing the external water pressure of the tunnel lining of the water-rich stratum by using the testing equipment are as follows:
A. filling and compacting one or more layers of simulated soil samples into the test box body to enable the total height of the simulated soil samples to reach a set height;
B. opening a valve of the water inlet pipe, and injecting water into the test box body until the simulated soil sample is saturated, wherein the water level is gradually higher than the height of the simulated soil sample;
C. opening the valve of the selected drain pipe, and adjusting the opening degree of the valve of the drain pipe to enable the drain pipe to drain water at a set drainage speed; simultaneously adjusting the opening degree of a valve of the water inlet pipe until the water level is stabilized to a set height; and the signal acquisition and analysis system acquires and processes the signal measured by the water pressure sensor at the moment to obtain the external water pressure value of the tunnel lining.
D. Changing the simulated soil sample and the height of the simulated soil sample layer by layer, changing the selected drain pipe and the opening degree thereof, and changing the set height of the water level; and (6) repeating the operation of the step A, B, C to obtain the external water pressure value of the tunnel lining of the water-rich stratum under the conditions of different surrounding rock types, different lining burial depths, different water heads and different water drainage.
The technical scheme is suitable for external water pressure test of the tunnel lining of the water-rich stratum by adopting drainage measures (a blind ditch, a drainage hole and a drainage ditch are built on the lining); or testing the external water pressure of the tunnel lining under the condition that water leakage exists on the slope of the water-rich mountain stratum.
Compared with the prior art, the utility model has the beneficial effects that:
firstly, different simulated soil samples and the heights of the simulated soil samples are buried layer by layer in a test box body, water levels with different heights are filled, and then water-rich stratum environments such as surrounding rocks with different structures, different lining burial depths, water bottoms of static water with different water heads, mountains, wetlands and the like in which water-rich tunnels are lined can be simulated conveniently, simply and vividly. And the external water pressure value of the rich water tunnel lining under various stratum static water environments is simulated by measuring through a plurality of water pressure sensors. The measured external water pressure value is closer to the water pressure value of the tunnel lining in the actual engineering, so that more accurate test basis can be provided for the water pressure resistant waterproof design, construction and maintenance of the water-rich stratum tunnel; and further, the safe operation of the tunnel is better ensured.
The water inlet pipe at the top of the test box body is provided with a valve, the drain pipes of the box cylinder and the bottom box cylinder are provided with a valve and a flow rate meter, and various dynamic water environments where different tunnel linings are located can be simulated by adjusting the water inlet pipe valve and different drain pipe valves and opening degrees thereof in a matching way and combining the drain speed measured by the flow rate meter:
(1) the drain pipe of the opened valve is the drain pipe of the bottom box barrel, so that the dynamic water-rich stratum environment under the tunnel drainage condition corresponding to the tunnel lining adopting drainage measures can be simulated;
(2) the drainage pipe of the valve is opened to be the drainage pipe of the box barrel in the middle, so that the dynamic mountainous body water-rich stratum environment under the condition that water leakage exists at one or more heights of the water-rich mountains can be simulated;
(3) the drain pipe of the opened valve is the drain pipe of the uppermost box cylinder, so that the dynamic water-rich stratum environment of the tunnel lining under the flowing water body (river, underground river) can be simulated;
the three dynamic water environments can be combined at will, so that various dynamic water-rich stratum environments of a tunnel, drainage measures and/or mountain seepage water and/or flowing water bodies can be simulated, and setting operations of different soil samples, heights and different water heads are combined, so that the device and the method disclosed by the utility model are wide in application range, and can be used for testing the external water pressure of the tunnel lining in a static water environment; but also can be used for testing the external water pressure of tunnel lining in various dynamic water-rich stratum environments.
The utility model can simply and conveniently test the external water pressure values of the tunnel lining under different surrounding rocks, different water head heights, different water body flowing conditions (different static, dynamic and dynamic conditions) and different tunnel drainage conditions, and further can analyze the relation and the law between the external water pressure of the tunnel lining and the surrounding rock type, the water head height, the water body flowing conditions and the tunnel drainage conditions according to the tested external water pressure values. The relation between the external water pressure of the tunnel lining and the permeability coefficient of the stratum where the tunnel lining is located can be analyzed and obtained by combining the permeability coefficient measured by a constant head permeameter on the simulated soil sample used in the test; and further provides richer and reliable test basis for researching the mechanism and rule of the water pressure resistance and the waterproofness of the tunnel in the water-rich stratum.
The cylindrical test box body is formed by splicing a bottom box barrel with a bottom and a plurality of sections of box barrels without bottoms, so that the box barrels with corresponding sections can be spliced into the box barrels according to different lining burial depths, and the test box body is flexibly and conveniently suitable for external water pressure tests of tunnel linings with various stratum heights.
All parts and simulation materials of the testing equipment are modularly arranged on the testing box body extending in one dimension, the structure is simple, the assembly and the operation are easy, the testing error is small, and the testing result is more accurate and reliable.
Furthermore, the test box body is made of organic glass.
Therefore, the position and seepage condition of water entering the test box body in the simulated soil sample can be observed more visually, dynamically and clearly, the opening degree of the valve and the control of the water level height are facilitated, and the formation and the change of the water environment of the water-rich stratum and the observation and analysis of the pressure relation of the water environment and the tunnel lining outer water are facilitated.
Further, the specific mode of splicing the bottom box barrel and the plurality of sections of bottomless box barrels is as follows: the bottom box barrel, the bottomless box barrel and the bottomless box barrel are connected by adopting a thread with a sealing ring or are bonded in a clamping manner.
Therefore, the splicing of the box barrels can be simply and conveniently realized.
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Drawings
Fig. 1 is a schematic sectional structure view of a test apparatus (threaded connection) according to example 1 of the present invention.
Fig. 2 is a schematic sectional view showing the structure of the test apparatus (clamp bonding) according to example 2 of the present invention.
Detailed Description
Example 1
Fig. 1 shows that, according to a specific embodiment of the present invention, an external water pressure testing apparatus for a water-rich stratum tunnel lining includes a test box, a tunnel lining model 2 in the test box, and is characterized in that:
the tunnel lining model 2 is arranged at the bottom of a cylindrical test box body, more than four water pressure sensors 3 are arranged on the outer side of the tunnel lining model 2, and output lines of the water pressure sensors 3 penetrate through the test box body to be connected with a signal acquisition and analysis system 8; one or more layers of simulated soil samples 4 are embedded in the test box body above the tunnel lining model 2;
the cylindrical test box body is formed by splicing a bottom box barrel 1a with a bottom and a plurality of sections of box barrels 1b without bottoms; the top of the test box body is provided with a water inlet pipe 5 with a valve; the bottom box barrel 1a and the bottom box barrel 1b are both provided with a water drainage pipe 6 with a valve, and the water drainage pipe 6 is provided with a flow meter 7.
The test box of this example is made of organic glass.
The specific way of splicing the bottom box tube 1a and the plurality of sections of bottomless box tubes 1b in the embodiment is as follows: the bottom tank barrel 1a, the bottomless tank barrel 1b and the bottomless tank barrel 1b are connected through threads with sealing rings.
The operation steps and the working process of testing the external water pressure of the tunnel lining by using the external water pressure testing equipment of the tunnel lining of the water-rich stratum of the embodiment are as follows:
A. filling and compacting one or more layers of simulated soil samples 4 into a test box body to ensure that the total height of the simulated soil samples 4 reaches a set height;
B. opening a valve of the water inlet pipe 5, and injecting water into the test box body until the simulated soil sample 4 is saturated, wherein the water level is higher than or equal to the height of the simulated soil sample 4, and the water level is stabilized to a set height; closing the valve of the water inlet pipe 5; the signal acquisition and analysis system 8 acquires and processes the signal of the water pressure sensor 3 at the moment to obtain the external water pressure value of the tunnel lining;
C. changing different simulated soil samples 4 and the heights of the simulated soil samples 4 layer by layer, and changing the set height of the water level; and (6) repeating the operation of the step A, B to obtain the outer water pressure values of the tunnel lining of the water-rich stratum under different surrounding rock types, different lining burial depths and different water heads.
The test method is suitable for testing the external water pressure of the tunnel lining of the water-rich stratum under the static water environment that the water body is in a static state or the flow of the water body is negligible and the tunnel lining does not adopt drainage measures.
Example 2
Fig. 2 shows, an outer water pressure test equipment of rich water stratum tunnel lining, tunnel lining model 2 in including experimental box, its characterized in that:
the tunnel lining model 2 is arranged at the bottom of a cylindrical test box body, more than four water pressure sensors 3 are arranged on the outer side of the tunnel lining model 2, and output lines of the water pressure sensors 3 penetrate through the test box body to be connected with a signal acquisition and analysis system 8; one or more layers of simulated soil samples 4 are embedded in the test box body above the tunnel lining model 2;
the cylindrical test box body is formed by splicing a bottom box barrel 1a with a bottom and a plurality of sections of box barrels 1b without bottoms; the top of the test box body is provided with a water inlet pipe 5 with a valve; the bottom box barrel 1a and the bottom box barrel 1b are both provided with a water drainage pipe 6 with a valve, and the water drainage pipe 6 is provided with a flow meter 7.
The test box of this example is made of organic glass.
The specific way of splicing the bottom box tube 1a and the plurality of sections of bottomless box tubes 1b in the embodiment is as follows: the bottom tank 1a, the bottomless tank 1b and the bottomless tank 1b are bonded by a clamp. Namely, a clamp 9 is sleeved outside the connecting part of the two sections of the box cylinder, and an adhesive is coated between the clamp 9 and the outer wall of the box cylinder.
The operation steps and the working process for testing the tunnel lining external water pressure by using the water-rich stratum tunnel lining external water pressure measuring device of the embodiment are as follows:
A. filling and compacting one or more layers of simulated soil samples 4 into a test box body to ensure that the total height of the simulated soil samples 4 reaches a set height;
B. opening a valve of the water inlet pipe 5, and injecting water into the test box body until the simulated soil sample 4 is saturated, wherein the water level is gradually higher than the height of the simulated soil sample 4;
C. opening the valve of the selected drain pipe 6, and adjusting the opening degree of the valve of the drain pipe 6 to enable the drain pipe 6 to drain water at a set drainage speed; simultaneously, adjusting the opening degree of a valve of the water inlet pipe 5 until the water level is stabilized to a set height; and the signal acquisition and analysis system 8 acquires and processes the signal measured by the water pressure sensor 3 at the moment, so that the external water pressure value of the tunnel lining is obtained.
D. Replacing the simulated soil sample 4 and the height of the simulated soil sample 4 layer by layer, changing the selected drain pipe 6 and the opening degree thereof, and changing the set height of the water level; and (6) repeating the operation of the step A, B, C to obtain the external water pressure value of the tunnel lining of the water-rich stratum under the conditions of different surrounding rock types, different lining burial depths, different water heads and different water drainage.
The test method is suitable for testing the external water pressure of the tunnel lining of the water-rich stratum under various dynamic water environments in which the lining adopts drainage measures (blind ditches, drainage holes and drainage ditches are built on the lining) and/or mountain seepage water and/or water flows.
Claims (3)
1. The utility model provides a rich water stratum tunnel lining's outer water pressure test equipment, tunnel lining model (2) in including experimental box, the experimental box, its characterized in that:
the tunnel lining model (2) is arranged at the bottom of a cylindrical test box body, more than four water pressure sensors (3) are arranged on the outer side of the tunnel lining model (2), and output lines of the water pressure sensors (3) penetrate through the test box body to be connected with a signal acquisition and analysis system (8); one or more layers of simulated soil samples (4) are embedded in the test box body above the tunnel lining model (2);
the cylindrical test box body is formed by splicing a bottom box barrel (1a) with a bottom and a plurality of sections of box barrels (1b) without the bottom; a water inlet pipe (5) with a valve is arranged at the top of the test box body; bottom case section of thick bamboo (1a) and case section of thick bamboo (1b) all be provided with drain pipe (6) of taking the valve, and install velocity of flow meter (7) on drain pipe (6).
2. The external water pressure test device for the tunnel lining of the water-rich stratum as claimed in claim 1, wherein: the test box body is made of organic glass.
3. The external water pressure test equipment for the tunnel lining of the water-rich stratum as claimed in claim 1, wherein the concrete way of splicing the bottom box barrel (1a) and the plurality of sections of bottomless box barrels (1b) is as follows: the bottom box barrel (1a), the bottomless box barrel (1b) and the bottomless box barrel (1b) are connected by adopting a thread with a sealing ring or a clamp type bonding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123020014.4U CN216524522U (en) | 2021-12-03 | 2021-12-03 | Outer water pressure test equipment of rich water stratum tunnel lining |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202123020014.4U CN216524522U (en) | 2021-12-03 | 2021-12-03 | Outer water pressure test equipment of rich water stratum tunnel lining |
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| CN216524522U true CN216524522U (en) | 2022-05-13 |
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| CN202123020014.4U Expired - Fee Related CN216524522U (en) | 2021-12-03 | 2021-12-03 | Outer water pressure test equipment of rich water stratum tunnel lining |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115839822A (en) * | 2023-02-27 | 2023-03-24 | 交通运输部公路科学研究所 | Test system and method for inducing mountain tunnel flooding and drainage process by heavy rainfall |
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2021
- 2021-12-03 CN CN202123020014.4U patent/CN216524522U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115839822A (en) * | 2023-02-27 | 2023-03-24 | 交通运输部公路科学研究所 | Test system and method for inducing mountain tunnel flooding and drainage process by heavy rainfall |
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Granted publication date: 20220513 |