Rock tension shear test device and method used in tension shear test machine

Abstract

The present invention aims at the lack of rock tension shear test equipment and provides a rock tension shear test device and method used in tension shear test machine. The device comprises a rightwards inverted U-shaped drawing part I, a rightwards inverted U-shaped drawing part II, an L-shaped guide slider I, an L-shaped guide slider II, a test machine loading head I, a test machine loading head II, a test machine loading head III and a test machine loading head IV. The rightwards inverted U-shaped drawing part I and the rightwards inverted U-shaped drawing part II enclose into an S-shaped area. A rock specimen is placed in the space S. The test machine loading head I applies predetermined normal force to the rock specimen; and test machine loading head II applies shearing force to the rock specimen. The load progress of is paid close attention to, once the rock specimen is damaged, a normal loading system is immediately shut down, and then a shear loading system is shut down to complete the test. The invention provides convenient, inexpensive and accurate test means for obtaining the mechanical characteristics of rock under the combined load of tension and shear.

Description

technical field [0001] The invention relates to a tensile-shear combined mechanical test of materials such as rocks. Background technique [0002] Tension-shear failure of rock is a common failure mode in rock mass engineering. For example, the excavation of deep caverns unloads the normal ground stress of the side wall and concentrates the tangential ground stress. When the unloading is very strong, tensile shear failure may occur. Another example is that the excavation and unloading of a rocky slope can lead to a tensile stress area on the upper slope, and the rock mass in this area is generally in a combined tension-shear stress state that is both tensioned and sheared. Another example is the landslides and earthquake landslides under the action of a large amount of self-weight, which show that the rear edge of the slope often suffers from tensile damage. Therefore, it is of great significance to study the mechanical properties of rock in tension and shear for the desig...

AI Technical Summary

Problems solved by technology

However, the cost of the first type of test equipment is very expensive. Although the cost of the second type is moderate, the test accuracy cannot be guaranteed due to the lack of control system (for example, the effect of the hydraulic jack to maintain a stable load is not good).

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