冻融循环作用下结构面剪切力学性质劣化规律研究

Study on the Degradation of Shear Mechanical Properties of Structural Planes under Freeze-thaw Cycles

岩石结构面的季节性冻融是影响岩石稳定性的主要因素之一。本文以寒区岩体工程为背景,开展了不同冻融循环次数(0~5次)、不同剪切角度(45°、60°)下的结构面冻融循环剪切试验,研究了冻融循环下结构面的力学性质。研究结果表明:随着冻融次数的不断增加,结构面的剪切强度、剪切模量、粘聚力和内摩擦角不断降低,剪应变不断增大,剪切强度的下降主要是由于粘聚力下降引起的,剪切角度较高的结构面塑性变形特征更加明显。研究成果可为寒区岩体边坡稳定性分析提供理论与试验支持。

Seasonal freeze-thaw of rock structural planes is one of the main factors affecting rock stability.This article takes rock mass engineering in cold regions as the background and conducts freeze-thaw cyclic shear tests on structural planes under different freeze-thaw cycles(0-5 times)and different shear angles(45°,60°)to study the mechanical properties of structural planes under freeze-thaw cycles.The results show that the Shear strength,Shear modulus,cohesion and internal friction angle of the structural plane are decreasing and the shear strain is increasing with the increase of freeze-thaw cycles.The decrease in shear strength is mainly caused by a decrease in cohesion.The plastic deformation characteristics of structural surfaces with higher shear angles are more obvious.The research results can provide theoretical and experimental support for the stability analysis of rock slopes in cold regions.