Surrounding rock stress disturbance degree test device

Abstract

The invention relates to a testing device for surrounding rock stress disturbance degree. The object of the present invention is to provide a surrounding rock stress disturbance degree testing device, which can evaluate the stress disturbance degree of surrounding rock simply, quickly and directly without affecting the state of surrounding rock. The technical solution of the present invention is: an isolation device placed in the surrounding rock borehole and a gas supply device placed outside the surrounding rock, the isolation device includes two packers for sealing the surrounding rock borehole, two packers A cavity in the pressure section is formed between the spacers, and the gas supply device includes a nitrogen tank, which is connected to a multi-way switch through an air delivery pump, an air delivery pipe, a flow sensor, and a check valve, and is divided into three branches through the multi-way switch. , one branch is connected to the cavity of the pressure section through the gas pipeline, and the other two branches are respectively connected to two packers through the gas pipeline, and the gas pipeline of each branch is equipped with a stop valve and a pressure relief valve; The changeover switch is provided with a pressure sensor for detecting the air pressure in each air pipe, and the pressure sensor is electrically connected with the pressure gauge and the recorder.

Description

technical field [0001] The invention relates to a testing device for surrounding rock stress disturbance degree. Applicable to the field of underground engineering. Background technique [0002] After the excavation of underground engineering, the surrounding rock will have stress redistribution, and the redistribution of stress will lead to irrecoverable damage in the surrounding rock. These damages are mainly caused by the expansion of internal cracks, so the internal structure of the surrounding rock will also have permanent Variety. The changes in the mechanical and hydraulic properties of the surrounding rock caused by these changes can be directly quantitatively tested, such as crack number statistics, acoustic wave testing, acoustic emission monitoring, penetration testing, etc. [0003] Because the surrounding rock is affected by stress redistribution differently, there will also be different disturbance degrees in the stress disturbance area of ​​the surrounding r...

AI Technical Summary

Problems solved by technology

Due to the difference in the degree of stress disturbance, the above-mentioned test methods generally have certain limitations when they are applied to the field. For example, only when the crack opens can the wave velocity decrease. Small or even tightly closed, it will not cause changes in the wave velocity of the surrounding rock

For another example, when using water permeability change test, the change of rock hydraulic properties will lead to inaccurate secondary test, especially for soft rock, this effect is more obvious, and even lead to the inability to complete subsequent tests

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