CN209911102U - Triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting - Google Patents
Triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting Download PDFInfo
- Publication number
- CN209911102U CN209911102U CN201920483581.7U CN201920483581U CN209911102U CN 209911102 U CN209911102 U CN 209911102U CN 201920483581 U CN201920483581 U CN 201920483581U CN 209911102 U CN209911102 U CN 209911102U
- Authority
- CN
- China
- Prior art keywords
- pressure chamber
- triaxial
- hydraulic sleeve
- simulating
- sample
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
A triaxial test pressure chamber capable of simulating unloading and supporting of underground caverns and tunnels in excavation comprises a triaxial pressure chamber body, and is used for containing samples and providing confining pressure and axial pressure. And the inner hydraulic sleeve is arranged in the inner pore passage of the sample and used for providing confining pressure with variable inner side and simulating stress change in the excavation and reinforcement processes. The outer side hydraulic sleeve is arranged on the outer side of the sample and used for providing outer side confining pressure and simulating a ground stress field where the underground rock body is located. The base, with the telescopic interface butt joint of inboard hydraulic pressure, hydraulic oil gets into the telescopic interface of inboard hydraulic pressure from the oil inlet through the base, provides the confined pressure that the inboard can change. And the axial displacement sensor is positioned at the top of the triaxial pressure chamber body and is used for measuring the axial deformation in the triaxial test. The utility model is used for the off-load of simulation on-the-spot underground cavern and tunnel excavation and the condition of strutting, the mechanical properties and the destruction characteristic of more accurate grasp tunnel country rock in excavation off-load and reinforcement process.
Description
Technical Field
The utility model belongs to geotechnical engineering mechanical test instrument field relates to a triaxial test pressure chamber that can simulate underground cavern and tunnel excavation off-load and strut.
Background
In order to research the physical and mechanical properties of a rock mass under natural conditions, the natural environment of the rock mass needs to be simulated, and although the environment of the rock mass can be well restored through a field in-situ test, the difficulty is high in the implementation process, and some factors cannot be controlled, so that the environment of the rock mass needs to be simulated in a laboratory.
The excavation of the underground cavern destroys the original stress balance condition, causes the redistribution of the stress of the surrounding rock mass, and causes the stress concentration phenomenon at the periphery of the cavern. At this time, if the stress field of each point of the tunnel wall does not exceed the critical value which can cause the rock mass to be damaged, the surrounding rock is stable, otherwise, the phenomena of relaxation deformation, even collapse damage and the like occur, and the surrounding rock gradually develops into the rock mass along the radius direction from the tunnel wall. In order to prevent the loose deformation and damage of the surrounding rock, the supporting is required to be carried out in time. The pressure acting on the support is called the pressure of the mountain rock or the pressure of the surrounding rock. Excavation of the underground cavern produces secondary stresses that behave radially as unloading and tangentially as loading. For such engineering, if the related theories and rock mechanics parameters obtained from the previous loading tests are still adopted to solve the problems, some errors and mistakes are necessarily caused. Therefore, the method has important theoretical and practical significance for researching the deformation, the strength property and the rock mechanical parameters of the rock under the unloading condition.
At present, in a triaxial unloading test of a laboratory, loading is generally carried out to an initial stress state, then axial pressure is controlled to be constant, and confining pressure is gradually reduced until a rock sample is damaged. In the test mode, the rock sample is solid, the loading and unloading of the lateral stress can simulate the unloading condition of the site slope excavation, but the unloading of the excavation of an underground cavern and a tunnel cannot be simulated. The existing various triaxial pressure chambers can only simulate the excavation unloading of a side slope or a foundation pit rock mass, but cannot simulate the excavation unloading and supporting of an underground cavern. The main reason is that the side slope or the foundation pit is the excavation of the surface rock soil body, and the stress change process of excavation unloading can be simulated by controlling the lateral stress loading and unloading of the sample in the test process; however, the excavation of underground engineering is carried out in rock mass, and the stress path is greatly different from that of the conventional triaxial unloading test. If the excavation of underground engineering is to be well simulated in the test process, the following two aspects should be realized: on one hand, lateral stress is applied to the outer side of the sample, and the ground stress field of the underground rock mass is simulated; and on the other hand, a variable stress field is applied to the interior of the rock sample to simulate the stress change in the excavation and reinforcement process.
Disclosure of Invention
The utility model aims to solve the technical problem that on the basis of current triaxial compression test room, a triaxial test compression chamber that can simulate underground cavern and tunnel excavation off-load and strut is provided for the off-load of simulation on-the-spot underground cavern and tunnel excavation and the condition of strutting, the mechanical properties and the destruction characteristic of more accurate grasp tunnel country rock in excavation off-load and reinforcement process. The triaxial test pressure chamber can simulate the excavation unloading of an underground cavern and can also simulate the support and disturbance after the excavation unloading.
The utility model discloses the technical scheme who takes does:
a triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting comprises:
the triaxial pressure chamber body is used for containing a sample and providing confining pressure and axial pressure;
the inner side hydraulic sleeve is arranged in an inner pore passage of the sample and used for providing confining pressure with variable inner side and simulating stress change in the excavation and reinforcement processes;
the outer hydraulic sleeve is arranged on the outer side of the sample and used for providing outer confining pressure and simulating a ground stress field where the underground rock mass is located;
the base is in butt joint with the interface of the inner side hydraulic sleeve, and hydraulic oil enters the interface of the inner side hydraulic sleeve through the oil inlet of the base to provide confining pressure with changeable inner side.
And the axial displacement sensor is positioned at the top of the triaxial pressure chamber body and is used for measuring the axial deformation in the triaxial test.
The upper end of the inner side hydraulic sleeve is closed, the lower end of the inner side hydraulic sleeve is provided with an inner side hydraulic sleeve interface with threads, the inner side hydraulic sleeve interface is in butt joint with the base, the base is in butt joint with the inner side hydraulic sleeve interface, the base is arranged on a bottom plate of a fixed rod connected with an axial displacement sensor, and the bottom plate is in contact with a pressure bearing table at the bottom end and is located in the center of the pressure bearing table.
The triaxial pressure chamber body comprises a top plate, two wings of the top plate extend out, a cylindrical metal block is arranged at the lower end of the top plate and connected with the top plate, a groove is formed in the middle of the cylindrical metal block, and the diameter of the groove is the same as that of the inner side hydraulic sleeve.
The cylindrical metal block at the lower end of the top plate is in contact with the sample and pressed on the sample, and the axial displacement sensor is in contact with the top plate.
The triaxial pressure chamber body is including taking screwed upper screw cap, lower screw cap, the screw cap can be screwed up through the rotation for the inside sample of fixed triaxial pressure chamber body.
The triaxial pressure chamber body comprises a pressure chamber side wall, an outer side hydraulic sleeve is arranged in the pressure chamber side wall, and a sample is arranged in the outer side hydraulic sleeve.
The sample is hollow cylindrical sample, and the external diameter is 50mm, and is high for 100mm, and the aperture of inside pore is 10 ~ 40mm, and the height of round hole is the height of rock specimen promptly, and the inside of sample is arranged in to inboard hydraulic pressure sleeve.
The first strain gauge is attached to the contact position of the outer portion of the sample and the outer side hydraulic sleeve, and the second strain gauge is attached to the contact position of the inner portion of the sample and the inner side hydraulic sleeve and used for measuring circumferential deformation during testing.
The diameter of the inner side hydraulic sleeve is the diameter of the circular hole, and the height is the height of the sample.
The base is a base with a threaded interface groove, the threaded interface is in butt joint with an interface of the inner side hydraulic sleeve to form a communicated area, and an oil inlet is formed in the lower portion of the base and connected with the hydraulic oil pump.
The two ends of the side wall of the pressure chamber of the triaxial pressure chamber body are respectively provided with an exhaust valve and a pressure chamber oil inlet, the pressure chamber oil inlet is externally connected with an oil pipe, and the oil pipe is connected with a hydraulic oil pump.
The utility model relates to a can simulate triaxial test pressure chamber of underground cavern and tunnel excavation off-load and strut, can simulate the excavation off-load and the strut condition of on-the-spot underground cavern and tunnel, simulation disturbance that can also step forward and reinforcement, operation process is simple, and the loading mode is simple, and simulation effect is better.
Drawings
The invention will be further explained with reference to the following figures and examples:
fig. 1 is a schematic view of the overall front view structure of the present invention.
Fig. 2 is a schematic diagram of the overall structure of the sample and the inner hydraulic sleeve of the present invention.
Fig. 3 is a schematic diagram of the general structure of the butt joint of the inner hydraulic sleeve and the base according to the present invention.
Fig. 4 is a schematic front view of the triaxial pressure chamber portion according to the present invention.
Fig. 5 is a schematic diagram of the overall structure of the triaxial pressure chamber portion according to the present invention.
Fig. 6 is a schematic view of the screw cap structure of the present invention.
In the figure: the device comprises a top plate 1, an axial displacement sensor 2, an inner hydraulic sleeve 3, an outer hydraulic sleeve 4, an exhaust valve 5, a fixing rod 6, a base 7, a bottom plate 8, a pressure bearing table 9, an upper screw cap 10, a lower screw cap 10 ', a pressure chamber side wall 11, a sample 12, a pressure chamber oil inlet 13, a first strain gauge 14, a second strain gauge 14 ', an inner hydraulic sleeve interface 15, an oil inlet 16, an upper screw cap interface 17, a lower screw cap interface 17 ' and a triaxial pressure chamber body 18.
Detailed Description
The invention will be further explained with reference to the drawings and the detailed description below:
(1): the diameter of triaxial test rock specimen should be 48mm ~ 54mm, and the ratio of sample height and diameter should be 2.0 ~ 2.5, and the rock specimen that generally uses is diameter 50mm, and high 100mm, and it is right to take this as an example the utility model discloses a multi-functional triaxial test pressure chamber explains. As shown in fig. 2, a circular hole having a diameter of 10 to 40mm was drilled in the center of the standard rock sample by a drill, and at this time, the preparation of the sample 12 was completed.
(2): the first strain gauge 14 and the second strain gauge 14' are respectively attached to the middle of the contact position between the outer part of the sample 12 and the outer hydraulic sleeve 4 and the middle of the contact position between the inner part of the sample 12 and the inner hydraulic sleeve 3. A resistance strain gauge is used as a testing device, and a Wheatstone bridge half-bridge circuit is adopted for connection. After the examination, the sample 12 with the two strain gauges was placed in the middle of the outer hydraulic sleeve 4 of the pressure chamber. As shown in fig. 1, 3, 4, 5, the lower screw cap interface 17 'is mated with the lower screw cap 10' and rotated to tighten. Then the base 7 is butted and screwed with the inner side hydraulic sleeve connector 15, and the base oil inlet 16 is connected to a hydraulic oil pump. The entire tri-axial pressure chamber body 18 is placed on the bottom plate 8, the upper lid interface 17 is docked with the upper lid 10 and rotated to be tightened, and then the top plate 1 is placed on the upper lid 10. The axial displacement sensor 2 is adjusted so that the initial reading of the axial displacement sensor 2 is within the error tolerance. Finally, the whole triaxial pressure chamber body 18 with the sample 12 is placed on the middle of the pressure bearing table 9, and an oil pipe connected with the hydraulic oil pump is connected to an oil inlet 13 of the pressure chamber and is screwed tightly. And (4) after the cable connected with the strain gauge and the cable of the whole triaxial testing machine are connected completely, the simulation test can be carried out.
(3): when in loading, two sets of independent lateral loading systems are used for loading, so that the internal pressure and the external pressure are synchronously applied, namely, the oil is simultaneously filled into the outer side hydraulic sleeve 4 and the inner side hydraulic sleeve 3 through the pressure chamber oil inlet 13 and the base oil inlet 16, and the oil is enabled to be filled into the outer side hydraulic sleeve 4 and the inner side hydraulic sleeve 3 simultaneouslyOutside oil pressure sigma3And inner oil pressure σ'3At the same time, the initial stress value is reached, where3＝σ3' i.e., the initial ground stress level is simulated.
(4): taper down σ 'by inboard side loading system'3To 0MPa and maintaining the outside oil pressure sigma3And is not changed. In the process, the axial deformation and the annular deformation of the sample are measured through the axial displacement sensor 2 and the strain gauge, the relation between stress and strain is researched, and the excavation unloading process of the underground cavern and the tunnel on site can be simulated.
(5): sigma 'can also be gradually increased from 0MPa through an inner side lateral loading system'3', and maintaining the outside oil pressure σ3Does not change, can be increased to sigma3The size is the same, and can be increased to slightly larger than sigma3Or slightly less than sigma3. In the process, the axial deformation and the circumferential deformation of the sample are measured through the axial displacement sensor 2 and the strain gauge, the relation between stress and strain is researched, and the prestress reinforcement (support) process after unloading of the underground cavern and the tunnel in the field can be simulated.
(6): sigma 'can also be increased at any time through an inner side lateral loading system'3While reducing sigma'3And maintaining the outside oil pressure sigma3And is not changed. The time and rate of the continuous increase and decrease is user dependent. In the process, the axial deformation and the annular deformation of the sample are measured through the axial displacement sensor 2 and the strain gauge, and the disturbance process after the unloading of the underground cavern and the tunnel in the field can be simulated according to the relation between the stress and the strain.
(7) After the test is finished, the testing machine stops working through a control switch, oil pipes at an oil inlet 13 of the pressure chamber and an oil inlet 16 of the base are removed, the axial displacement sensor 2 is removed from the fixed rod 6, the whole triaxial pressure chamber body 18 is moved away from a platform of the testing machine, the upper rotary cover 10 and the lower rotary cover 10' are unscrewed, the sample 12 is taken out from the outer side hydraulic sleeve 4 through a special sampler, two strain foils are removed, the inner side hydraulic sleeve 3 is taken out from the sample 12, the taken sample 12 is wrapped by a preservative film and bound by a rubber band so as to prevent chips from peeling off from a rock sample, other testing parts are wiped clean, and then the testing machine is placed well according to positions, removed from cables and cleaned.
Claims (9)
1. The utility model provides a triaxial test pressure chamber that can simulate underground cavern and tunnel excavation off-load and strut which characterized in that includes: the triaxial cell body (18) is used for containing a sample (12) and providing confining pressure and axial pressure;
the inner side hydraulic sleeve (3) is arranged in an inner pore passage of the sample (12), and the inner side hydraulic sleeve (3) is used for providing confining pressure with variable inner side and simulating stress change in the excavation and reinforcement process;
the outer hydraulic sleeve (4) is arranged on the outer side of the test sample (12), and the outer hydraulic sleeve (4) is used for providing outer confining pressure and simulating a ground stress field where an underground rock body is located;
the base (7) is in butt joint with the interface (15) of the inner side hydraulic sleeve (3), and hydraulic oil enters the interface (15) of the inner side hydraulic sleeve (3) through an oil inlet (16) of the base (7) to provide confining pressure with variable inner side;
the axial displacement sensor (2) is located at the top of the triaxial pressure chamber body (18), and the axial displacement sensor (2) is used for measuring axial deformation in a triaxial test.
2. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: inboard hydraulic sleeve (3) upper end is sealed, the lower extreme is equipped with and takes screwed inboard hydraulic sleeve interface (15), inboard hydraulic sleeve interface (15) dock with base (7), base (7) with inboard hydraulic sleeve interface (15) dock, base (7) are arranged in on bottom plate (8) of dead lever (6) that are connected with axial displacement sensor (2).
3. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: the triaxial pressure chamber body (18) comprises a top plate (1), two wings of the top plate (1) extend out, a cylindrical metal block is arranged at the lower end of the top plate and connected with the top plate, a groove is formed in the middle of the cylindrical metal block, and the diameter of the groove is the same as that of the inner side hydraulic sleeve (3).
4. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 3, wherein: the cylindrical metal block at the lower end of the top plate (1) is in contact with the sample (12) and is pressed on the sample (12), and the axial displacement sensor (2) is in contact with the top plate (1).
5. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: the triaxial pressure chamber body (18) comprises an upper screw cap (10) and a lower screw cap (10') which are provided with threads, and the screw caps can be screwed down through rotation and are used for fixing a sample (12) inside the triaxial pressure chamber body (18).
6. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: the triaxial cell body (18) comprises a cell side wall (11), an outer hydraulic sleeve (4) is disposed within the cell side wall (11), and a test specimen (12) is disposed within the outer hydraulic sleeve (4).
7. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: the first strain gauge (14) is attached to the contact position of the outer part of the test sample (12) and the outer side hydraulic sleeve (4), and the second strain gauge (14') is attached to the contact position of the inner part of the test sample (12) and the inner side hydraulic sleeve (3) and used for measuring the annular deformation during the test.
8. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: the base (7) is a base with a threaded interface groove, the threaded interface is in butt joint with an interface (15) of the inner side hydraulic sleeve (3) to form a communicated area, and an oil inlet (16) is formed in the lower portion of the base (7) and connected with a hydraulic oil pump.
9. The triaxial test pressure chamber capable of simulating unloading and supporting of underground cavern and tunnel excavation according to claim 1, wherein: two ends of a pressure chamber side wall (11) of the triaxial pressure chamber body (18) are respectively provided with an exhaust valve (5) and a pressure chamber oil inlet (13), the pressure chamber oil inlet (13) is externally connected with an oil pipe, and the oil pipe is connected with a hydraulic oil pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920483581.7U CN209911102U (en) | 2019-04-10 | 2019-04-10 | Triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920483581.7U CN209911102U (en) | 2019-04-10 | 2019-04-10 | Triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209911102U true CN209911102U (en) | 2020-01-07 |
Family
ID=69035772
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920483581.7U Active CN209911102U (en) | 2019-04-10 | 2019-04-10 | Triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209911102U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110006742A (en) * | 2019-04-10 | 2019-07-12 | 三峡大学 | A kind of triaxial test pressure chamber of analog underground chamber and tunnel excavation off-load and supporting |
| CN113463638A (en) * | 2021-06-22 | 2021-10-01 | 中铁五局集团第一工程有限责任公司 | Diversion branch tunnel construction method capable of carrying out water characteristic identification |
-
2019
- 2019-04-10 CN CN201920483581.7U patent/CN209911102U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110006742A (en) * | 2019-04-10 | 2019-07-12 | 三峡大学 | A kind of triaxial test pressure chamber of analog underground chamber and tunnel excavation off-load and supporting |
| CN113463638A (en) * | 2021-06-22 | 2021-10-01 | 中铁五局集团第一工程有限责任公司 | Diversion branch tunnel construction method capable of carrying out water characteristic identification |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104155175B (en) | Rock hollow cylinder torsional shear instrument | |
| US4579003A (en) | Instrument for testing earthen samples under triaxial load conditions | |
| CN110006742A (en) | A kind of triaxial test pressure chamber of analog underground chamber and tunnel excavation off-load and supporting | |
| CN209911102U (en) | Triaxial test pressure chamber capable of simulating underground cavern and tunnel excavation unloading and supporting | |
| CN201803962U (en) | Heterogeneous model computed tomography (CT) scan simulation device | |
| CN104833775B (en) | The threedimensional model experimental rig of the prominent mud geological disaster of simulation gushing water | |
| CN108709810B (en) | Test method for simulating underground rock excavation through air pressure unloading | |
| CN107449678A (en) | Large-scale triaxial shear test devices and methods therefor in situ | |
| CN103604702A (en) | Device for testing fracture toughness of rock | |
| WO2021088238A1 (en) | Shpb test system-based dynamic lateral strain measurement device and method for test piece | |
| CN107356481A (en) | It is used for the device for measuring Rock Poisson Ratio Using in a kind of three-axis infiltration experiment | |
| CN111366468B (en) | Side pressure electrical measurement test system and test method | |
| CN205175831U (en) | Rock triaxial rheology experimental apparatus based on true water environment | |
| CN108645565A (en) | A kind of binary channels SERVO CONTROL dynamic pore pressure marking apparatus and scaling method | |
| WO2021012371A1 (en) | Frameless triaxial rock test apparatus and operating method | |
| CN111521493A (en) | High-temperature triaxial rock creep testing machine capable of simultaneously loading in multiple stages and using method | |
| CN111811923A (en) | System and method for testing flexibility ratio of hysteretic elastic strain recovery method for ground stress measurement | |
| CN114965077A (en) | Automatic high-precision rock expansion test device and application method thereof | |
| CN103091160B (en) | Geotechnical compression test hydraulic system and testing method | |
| CN210604631U (en) | Indoor tester for high water content dredged soil under low stress and negative pressure state | |
| CN111579377B (en) | Dynamic and static triaxial test device capable of eliminating influence of membrane embedding effect | |
| CN100557443C (en) | Natural leakage detector for micro crack state concrete | |
| CN207300760U (en) | A kind of large-scale triaxial shear test device in situ | |
| CN215065813U (en) | Engineering detects uses granular material strength test device | |
| CN115165585A (en) | Rock triaxial mechanical parameter testing device and method under carbon dioxide contact |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CB03 | Change of inventor or designer information | ||
| CB03 | Change of inventor or designer information |
Inventor after: Xiong Yu Inventor after: Li Tao Inventor after: Deng Huafeng Inventor after: Qi Yu Inventor after: Pan Deng Inventor after: Zhi Yongyan Inventor after: Duan Lingling Inventor before: Li Tao Inventor before: Deng Huafeng Inventor before: Qi Yu Inventor before: Xiong Yu Inventor before: Pan Deng Inventor before: Zhi Yongyan Inventor before: Duan Lingling |