Physical properties and shear strength characteristics of high liquid limit granite residual soil

High liquid limit granite residual soil (GRH) is widely distributed over South China. The physical properties and shear strength characteristics of the fine grained soil containing coarse of GRH are studied, including the natural components and soil fabric, physical features and indexes, shear peak strength and residual strength, etc. Based on a series of laboratory tests, the fine grain moisture content and its influences on liquidity index are analyzed, and the statistic relationships between coarse-grain content and field moisture as well as the physical indexes and shear strength parameters are also generalized. Through repeated direct shear tests, the major points for determining the residual strength by such test methods are discussed, and correspondingly, the typical shear curves of resistance at relatively large shear displacement are analyzed. The residual soil has combinational characteristics of both high liquid limit soil and coarse-grained soil, so it is important to understand its basic properties by studying the effects of coarse grain content.