CN-122016489-A - Indoor testing device and method for tensile strength of rock under in-situ condition

CN122016489ACN 122016489 ACN122016489 ACN 122016489ACN-122016489-A

Abstract

The embodiment of the application provides an indoor testing device and method for rock tensile strength under an in-situ condition, which belong to the technical field of rock mechanical testing and comprise a cavity, an experimental assembly structure, a control and display system, a confining pressure booster, a servo control device, a hydraulic station, a data acquisition system, a control and display system and a data acquisition system, wherein the experimental assembly structure is arranged in the cavity and comprises a chassis, a lower pressure head, an upper pressure head and a load sensor, the lower pressure head is fixedly connected to the chassis, the upper pressure head is fixedly connected with the load sensor, the upper pressure head and the lower pressure head are provided with axial deformation sensors, the confining pressure booster is connected with the cavity, the servo control device is connected with the cavity, the hydraulic station is connected with the confining pressure booster and the servo control device, and the data acquisition system is connected with the confining pressure booster, the servo control device and the axial deformation sensors. According to the indoor testing device and method for the tensile strength of the rock under the in-situ condition, the accuracy of testing the tensile strength of the rock can be improved.

Inventors

JU YINGTONG
FENG ZHISHAN
LIU XIAOLI
WANG CHENGWEN
LIU ZHIYUAN
WANG ZEFAN
ZHAO MINGXIN
XU QING
ZHOU RAN
PANG YIJIE

Assignees

清华大学
粤水电轨道交通建设有限公司
北京清研正德创新科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260326

Claims (8)

1. An indoor testing arrangement of rock tensile strength under normal position condition, characterized in that includes: A chamber; The experimental assembly structure is arranged in the cavity and comprises a chassis, a lower pressure head, an upper pressure head and a load sensor, wherein the lower pressure head is fixedly connected to the chassis, the upper pressure head is fixedly connected with the load sensor, and the upper pressure head and the lower pressure head are provided with axial deformation sensors; the confining pressure booster is connected with the cavity and is used for injecting confining pressure pressurizing medium into the cavity; the servo control device is connected with the cavity and used for applying axial pressure towards the experimental assembly structure; The hydraulic station is connected with the confining pressure booster and the servo control device and is used for providing hydraulic power for the confining pressure booster and the servo control device; the data acquisition system is connected with the axial deformation sensor and is used for acquiring data information generated by the axial deformation sensor; The control and display system is connected with the confining pressure booster, the servo control device and the data acquisition system and is used for controlling the confining pressure booster and the servo control device to start or stop running and receiving and displaying the data information.
2. The in-situ rock tensile strength testing device of claim 1, wherein the testing device further comprises: The separation pad is arranged between the upper pressure head and the sample and between the lower pressure head and the sample, and comprises a first plate body and a second plate body arranged around the first plate body, wherein the first plate body and the second plate body are enclosed to form a first area and a second area which are provided with openings, and the first area and the second area are respectively positioned at two sides of the first plate body; The first region is configured to surround an end of the sample, and the second region is configured to contact the upper ram or the lower ram.
3. The in-situ rock tensile strength testing device according to claim 2, wherein: the volume of the first region is greater than the volume of the second region.
4. The in-situ rock tensile strength testing device according to claim 2, wherein: The first plate body is provided with an opening, and the opening penetrates through the first plate body.
5. The in-situ rock tensile strength indoor test device according to claim 1, wherein: the chassis is provided with a fixed groove, the end part of the lower pressure head is positioned in the fixed groove, and the lower pressure head is fixedly connected with the fixed groove through threads; The upper pressure head is connected with the load sensor through a bolt.
6. The in-situ rock tensile strength indoor test device according to claim 1, wherein: the chassis is provided with a plurality of signal transmission channels, and the axial deformation sensor is connected with the data acquisition system through the signal transmission channels.
7. An indoor test method for rock tensile strength under in-situ conditions, which is applied to an indoor test device for rock tensile strength under any one of claims 1-6, and is characterized in that the method comprises the following steps: mounting a sample between an upper ram and a lower ram of the testing device, lowering a chamber of the testing device from directly above an experimental assembly structure of the testing device, and enclosing the experimental assembly structure; Loading the sample by using a confining pressure booster of the testing device and a servo control device; and lifting the upper pressure head until the sample is damaged, and recording an axial load value and an initial loading load value at the moment to obtain the tensile strength of the sample.
8. The in-situ rock tensile strength testing method of claim 7, wherein in said step of mounting a sample between an upper ram and a lower ram of said testing device, said testing method further comprises: The outside of sample parcel latex membrane and pyrocondensation pipe in proper order, the latex membrane with the both ends of pyrocondensation pipe extend respectively to go up the pressure head with the position of pressure head down, and utilize the sealing washer will latex membrane with the both ends of pyrocondensation pipe respectively with go up the pressure head with pressure head sealing connection down.

Description

Indoor testing device and method for tensile strength of rock under in-situ condition Technical Field The application relates to the technical field of rock mechanics testing, in particular to an indoor testing device and method for rock tensile strength under in-situ conditions. Background At present, in large engineering construction, stress release caused by excavation of a cavity is often involved, and then a situation that a tensile stress state exists locally is caused, and the rock-soil material has the characteristic that the compressive strength is far higher than the tensile strength, so that potential safety risks can be brought to engineering construction. In the same way, the stability check of the surrounding rock of the well wall is an important link for ensuring safe and rapid production in the oil gas drilling and production process, and the cement structure is ensured to be in a compressive stress state for a long time in the bridge construction process in a mode of applying prestress. Therefore, determining the true tensile strength of the geotechnical material under the actual working condition has important significance for improving the safety of various infrastructures and resource exploitation projects. However, the current method for obtaining the tensile strength of the rock has larger errors. Disclosure of Invention The embodiment of the application provides an indoor testing device and method for testing the tensile strength of rock under an in-situ condition, aiming at improving the accuracy of testing the tensile strength of the rock. A first aspect of an embodiment of the present application provides an indoor test apparatus for testing tensile strength of rock under in-situ conditions, including: A chamber; The experimental assembly structure is arranged in the cavity and comprises a chassis, a lower pressure head, an upper pressure head and a load sensor, wherein the lower pressure head is fixedly connected to the chassis, the upper pressure head is fixedly connected with the load sensor, and the upper pressure head and the lower pressure head are provided with axial deformation sensors; the confining pressure booster is connected with the cavity and is used for injecting confining pressure pressurizing medium into the cavity; the servo control device is connected with the cavity and used for applying axial pressure towards the experimental assembly structure; The hydraulic station is connected with the confining pressure booster and the servo control device and is used for providing hydraulic power for the confining pressure booster and the servo control device; the data acquisition system is connected with the axial deformation sensor and is used for acquiring data information generated by the axial deformation sensor; The control and display system is connected with the confining pressure booster, the servo control device and the data acquisition system and is used for controlling the confining pressure booster and the servo control device to start or stop running and receiving and displaying the data information. Optionally, the test device further comprises: The separation pad is arranged between the upper pressure head and the sample and between the lower pressure head and the sample, and comprises a first plate body and a second plate body arranged around the first plate body, wherein the first plate body and the second plate body are enclosed to form a first area and a second area which are provided with openings, and the first area and the second area are respectively positioned at two sides of the first plate body; The first region is configured to surround an end of the sample, and the second region is configured to contact the upper ram or the lower ram. Optionally, the volume of the first region is greater than the volume of the second region. Optionally, an opening is formed in the first plate body, and the opening penetrates through the first plate body. Optionally, a fixing groove is formed in the chassis, the end part of the lower pressure head is located in the fixing groove, and the lower pressure head is fixedly connected with the fixing groove through threads; The upper pressure head is connected with the load sensor through a bolt. Optionally, a plurality of signal transmission channels are formed in the chassis, and the axial deformation sensor is connected with the data acquisition system through the signal transmission channels. A second aspect of the embodiment of the present application provides an indoor test method for tensile strength of rock under in-situ conditions, which is applied to an indoor test device for tensile strength of rock under in-situ conditions as provided in the first aspect of the embodiment of the present application, and the method includes: mounting a sample between an upper ram and a lower ram of the testing device, lowering a chamber of the testing device from directly above an experimental assembly structure of the test