Rock Hollow Cylindrical Torsional Shear Instrument

Abstract

The invention relates to an indoor rock mechanics testing device, in particular to a rock hollow cylinder torsion shear apparatus capable of realizing complex stress path, and belongs to the technical field of geotechnical engineering techniques. The torsion shear apparatus comprises a base, a sleeve, a lower pressure head, an upper pressure head, a piston, an upper seat, a head cover, a connecting rod and a torsion device. The rock hollow cylinder torsion shear apparatus disclosed by the invention has the advantages that the puzzle that the stress path of the rock indoor testing device is single is solved; axial force, inner confining pressure, outer confining pressure and torque can be loaded on a rock sample separately or together; the defect that the four external forces interfere with one another during loading is overcome; the magnitude variation of principal stress or the rotating stress path of the principal axis of stress can be simulated; the rock hollow cylinder torsion shear apparatus is reasonable in structure, easy to manufacture, easy to operate, accurate in measuring system and high in automation degree and can be used for indoor tests of rock complex loading paths.

Description

technical field [0001] The invention relates to an indoor rock mechanics test device, in particular to a rock hollow cylinder torsional shear instrument capable of realizing complex stress paths, and belongs to the technical field of geotechnical engineering. Background technique [0002] During the site excavation of engineering rock mass, the stress state inside the rock mass is extremely complex, which is manifested as: the change of the principal stress when the direction of the principal axis of stress remains unchanged, the rotation of the principal axis of stress when the magnitude of the principal stress remains unchanged, the rotation of the direction of the principal axis of stress and the rotation of the principal stress Size changes. From a macroscopic point of view, the above-mentioned changes in the stress state will lead to plastic deformation of the rock mass, and changes in elastic parameters and strength parameters; from a microscopic point of view, micro-c...

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Problems solved by technology

4) The existing hollow cylindrical torsional shear instrument suitable for soil samples has problems of mutual influence between axial loading and torque loading structure, such as the friction effect caused by axial loading

[0005] To sum up, the existing rock laboratory test equipment cannot realize complex stress paths such as stress spindle rotation, and the test function is relatively simple; on the other hand, the hollow cylindrical torsional shear instrument suitable for soil samples cannot be applied to rock tests, and Due to the different properties of rock and soil, it cannot be modified for rock test

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