Testing device and method for rock straight shear-seepage

Abstract

The invention discloses a testing device and method for rock straight shear-seepage, and relates to a rock mechanics test technique. An involved three-axis compression shear testing device comprises an axial shear pressing head (1), a pressure chamber (3), sealing tape (4), a deformation rubber sleeve (5) for isolating contact between a test piece and oil, the testing test piece (6) with a prefabricated joint, and a rigid cylindrical base plate (8). According to the adopted testing method and test piece preparation method, the characteristics of a rock three-axis compression experiment are fully utilized, the stable confining pressure is provided for the test piece through the oil pressure chamber, the rock test piece with the prefabricated joint is prepared through the special method, meanwhile, the conditions for a shear test are created, and then a seepage test is carried out. By adopting the method to carry out the shear-seepage tests through a three-axis testing instrument, obtained data are more accurate and more reliable, and the shear damage condition of rock under the natural conditions is simulated to a larger extent.

Description

technical field [0001] The invention relates to a test device and method for direct shear-seepage of rock, in particular to a test method for shear-seepage by using rock triaxial compression test equipment. Background technique [0002] The coupling characteristics of seepage and shear in deep rock mass joints has become a key scientific problem that needs to be solved urgently in the stability analysis of large deep underground engineering. The full shear seepage coupling test of rock joints is the most effective and direct method to study the hydraulic characteristics of rock joints. The rock shear strength and shear strength parameters are the premise and basis for numerical simulation and stability analysis of surrounding rock deformation. [0003] At present, the test methods for rock shear strength mainly include direct shear test and triaxial shear test. [0004] The rock direct shear test device and test method are relatively simple, and can be carried out in the l...

AI Technical Summary

Problems solved by technology

However, there are many deficiencies in the determination of rock shear strength by conventional direct shear tests.

[0005] 1. The sample can only undergo shear failure along the pre-selected failure surface in the direct shear instrument, ignoring the internal defects of the sample, and can only simulate the shear failure of the rock under unidirectional compression;

[0006] 2. During the direct shear test, the normal stress on the sample will change with the increase of shear load and displacement, which cannot produce a stable confining pressure on the sample, and the measured shear strength may be too small ;

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