Static Shear and Liquefaction Potential of Sand

The state parameter, which describes the initial state of sand before shearing, combining with the concepts of critical stress ratio line and phase transform line are used to assess the characteristics of sand during shearing. The state parameter of each tested sample is determined after the steady state line is constructed, and then relations of characteristics of the cyclic deformation behavior and the state parameter of sand are discussed. The value of the lowest point, Sup1 on the CSR line in the p’ – q plot is related to ec for a specific sand. Once the stress path of monotonic or cyclic tests crosses the CSR line, strain softening may quickly occur. On the contrary, the stress path bends sharply upwards and to the right along the PT line if it touches the PT line. Liquefaction resistance may decrease with increasing the value of α for sand having ψ \u3e 0. Oppositely, it may increase with increasing the value it of α for sand having ψ \u3c 0. In the case of sand having ψ ≅ 0, nearly keeps no change with increasing the value of α