58 Quantitative Study on the Shear Strength Parameter of Undisturbed Loess

The shear mechanical property is discussed to build a frame using physical property of loess through the shear test and theory of undisturbed loess under the different moisture content and time. It explained the shear strength with macroscopically intensity parameter and microcosmic intensity parameter, including moisture content, dry density, porosity ratio and time. As the dry density increases, the shear strength of undisturbed loess under the different moisture content will scatter. The resistance of the undisturbed loess goes against the shear deformation under the different moisture content. The moisture content has greater sensitivity to the macroscopical intensity parameter, but porosity ratio and dry density have litter sensitivity to it. When w=25, under normal stress 300–400kPa, the macroscopical intensity parameter tends towards stability greatly, explaining the structural stability under this situation of soil. The macroscopical intensity parameter theory and microcosmic intensity parameter theory under the structural parameter theory is feasible. It's a new method to express structural intensity theory of soil, to realize a kind of structural ideas of soil correctly, a kind of way to describe structural intensity of soil to ration.