Testing method for testing compression-shear performance of jointed rock

Abstract

The invention discloses a testing method for testing the compression-shear performance of jointed rock. The method includes the following steps of preparing a tested test piece with a slope, putting the tested test piece on a test piece fixing base, exerting normal loads on the tested test piece, exerting inclined loads perpendicular to the slope on the tested test piece after the normal stress reaches a preset value, gradually increasing the inclined loads, reducing the load value of the normal loads, keeping the normal stress in the loading process unchanged, making the shear force increased continuously till the tested test piece is broken, and making the inclined loads and the normal loads intersect in the preset shear face of the tested test piece so that bending moment can be prevented from being generated in the loading process. The whole method is easy and convenient to implement; compared with the prior art, the method has the advantages that the bending moment can be prevented in the loading process, test errors are reduced, the accuracy of test results can be easily ensured, and the method is suitable for various civil engineering construction occasions and has the outstanding substantive advantages and remarkable progresses of being simple in structure, easy to manufacture, convenient to operate and the like.

Description

technical field [0001] The invention belongs to the field of rock tests, in particular to a test method for testing the compression-shear performance of jointed rock masses. Background technique [0002] In the field of geotechnical engineering, rock failure is usually shear failure. The bearing capacity of the building foundation, the earth pressure of the retaining wall and the underground structure, and the stability of various slopes are all controlled by the shear strength of the rock mass. Whether the shear strength of the rock mass can be obtained correctly is often the key to the success or failure of the project. key. [0003] Most scholars believe that the generation and expansion of cracks in rock mass is caused by the stress state at the crack position reaching a critical value. The stress can be tensile stress perpendicular to the crack plane or shear stress parallel to the crack plane. The mechanism of expansion and expansion can be explained from the perspec...

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Problems solved by technology

[0008] 1. For the application of shear force, the direct shear method is usually adopted, and the shear force is applied with the help of a fixed shear box. Because the size and joint position of the rock mass specimen during the cutting process are not easy to control, and the specimen during the test loading process It is easy to be unevenly stressed, causing the shear failure of the specimen to start from the edge of the specimen, which does not conform to the actual failure process of the rock mass under natural conditions, so that the obtained rock mechanical parameters deviate from the actual

[0009] 2. There is a bending moment in the loading process of the traditional shear test, which also leads to inaccurate test measurement data, and the size effect brought about by the increase of the specimen size makes this shortcoming more obvious

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