Sampling and indoor in-situ testing method for soft intercalated layer undisturbed sample

Abstract

The invention provides a sampling and indoor in-situ testing method for a soft intercalated layer undisturbed sample. By a top cement cover, a bottom cement cover and a sampling tube closed cube rock sample, the soft intercalated layer undisturbed sample is obtained; the tube wall of a sampling tube is peripherally subjected to truncation cutting in the middle of the sampling tube to form both an upper part and a lower part so as to form an upper disk and a lower disk of a shearing-resistant test; a top concrete cushion block and a bottom concrete cushion block are placed and the soft intercalated layer undisturbed sample is placed in a shear box of a direct shear apparatus, so that the upper disk is positioned in an upper shear box, and simultaneously, the lower disk is positioned in a lower shear box; a normal force is applied to the symmetry center of the top concrete cushion block, and simultaneously, a positive tangential force and a reverse tangential force are respectively applied to two opposite surfaces of the upper shear box and the lower shear box so as to carry out the shear-resisting test. The method is an in-situ test of a soft intercalated layer; shear strength and a shear strength testing result which are obtained by the test accord with the practical condition; accurate physical and mechanics parameters can be provided for stability analysis of a slope.

Description

technical field [0001] The invention relates to a sampling and testing method for a weak interlayer, and belongs to the technical field of slope stability analysis methods. Background technique [0002] Weak interlayers are rock formations with a certain thickness, low mechanical strength, large compression deformation, and easy softening when exposed to water. They are usually regarded as geological weak surfaces. The existence of weak interlayers has an impact on engineering. Interlayer damage. Most weak interlayers are quite different from the upper and lower strata in terms of macroscopic structure and material composition, resulting in significantly different engineering geological properties from the upper and lower strata. If there are weak interlayers in the rock mass of the slope, interlayer displacement deformation, twisting deformation or plastic extrusion deformation will easily occur, forming a potential slip surface, which often controls the failure mode of th...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome the problem in the prior art that the original sample shear strength parameters of the weak interlayer cannot be obtained in the laboratory, and provide a method for sampling and indoor in-situ testing of the weak interlayer original sample