Sound wave method testing method for tunnel surrounding rock loosening circle

Abstract

The invention provides a sound wave method testing method for a tunnel surrounding rock loosening circle. The method comprises the following steps: drilling a test drill hole in tunnel surrounding rock, arranging the grouting type bags on the upper inner wall and the lower inner wall of the drilled hole, placing the hole sealing pipe in the drilled hole, forming a grout overflowing opening and a grout outlet in the outer wall of the hole sealing pipe, enabling a testing instrument to penetrate through the hole sealing pipe, injecting grout into the grouting type bags through the grout outlet,and after grout in the grouting type bags reaches specific strength, injecting the slurry through the grout overflowing opening, injecting water into the hole sealing pipe, after the whole drilled hole is filled with the water, using the water as a coupling agent, using a testing instrument to emit sound waves to tunnel surrounding rock of the tunnel surrounding rock, and determining the range ofthe tunnel surrounding rock loosening circle according to the change condition of the reflection wave velocity of the tunnel surrounding rock. Aiming at complex geology, high ground stress areas and loose and broken surrounding rocks, the invention provides the method for testing the loose circle of the tunnel surrounding rocks by the acoustic wave method, the water plugging effect is improved through the hole sealing pipe, and the hole protection section ensures the drilling stability.

Description

technical field [0001] The invention relates to the technical field of acoustic wave testing of surrounding rock loose circles during tunnel construction, in particular to an acoustic wave testing method for surrounding rock loose circles of tunnels. Background technique [0002] In recent years, with the vigorous development of infrastructure and transportation engineering, more and more underground engineering constructions are moving towards complex geological environments such as deep burial and high ground stress. Therefore, the deformation mechanism of underground engineering rock mass is becoming more and more complex, the deformation of rock mass is intensified, and the damage of primary support is also becoming more serious, resulting in frequent occurrence of geological disasters in underground engineering, which seriously affects the rapid development of underground engineering construction. However, the test of rock mass loosening circle in underground engineerin...

AI Technical Summary

Problems solved by technology

However, for the geological environment with developed joints and fissures, weak and broken surrounding rocks, and high ground stress, it is relatively difficult to test the hole formation, and the hole collapse and blockage are serious, which affects the application range of the sonic method loose circle test technology

At the same time, water is used as the coupling agent for the loose circle test technology of the acoustic wave method. In the process of testing the loose circle of the rock mass in the arch of the underground project, it is often difficult to block the water and it is difficult to fill the test borehole, resulting in distortion of the test results.

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