考虑颗粒级配影响的滑带土宏观力学和微观结构特性研究

Macro Mechanical and Micro Structural Properties of Slip Zone Soil with Different Particle-Size Distributions

滑带土受滑坡变形演化的影响,其物质组成和结构性质存在空间变异性。滑带土的颗粒级配在不同部位表现出各向异性,可作为滑带空间变异性的直观指标,因此考虑滑带土颗粒级配影响下的宏观变形力学和微观结构特性有利于揭示滑坡真实的演化模式。以三峡库区典型滑坡——黄土坡滑坡的滑带土为研究对象,在保持土体本身自相似性的前提下,利用三轴固结不排水剪切试验和电镜扫描试验对不同颗粒级配影响下的滑带土的宏观变形力学和微观结构特性进行了研究。试验结果表明:颗粒级配分形维数对滑带土的强度参数和内部结构有显著的影响。

As slip zone soil is affected by landslide evolution,the material composition and structural properties of slip zone soil exhibits spatial variability.The particle-size distribution of the soil in different parts of the slip zone shows anisotropy,which can be taken as a direct index of spatial variation of slip zone.So the macro and micro properties of slip zone soil with different particle-size distribution should be considered in revealing the true evolution model of landslide.This paper takes the slip zone soil of a typical landslide in Three Gorges Reservoir area as the research object,adopts triaxial shear test and electron microscopy test to analyze the macro and micro properties,while maintaining the self-similarity characteristics of the soil.The experimental results show that fractal dimension value has a significant effect on strength parameters and inner structure of the samples.