Coupled effect of confining stress and static shear in cyclic resistance of tailing sands

Abstract

Nowadays, the high levels of copper production generates significant amounts of waste called tailings. In response to the latter, there is an increased need to understand the tailings behaviour in order to ensure the mechanical stability of dams. In this context, it is of great importance to study the resistance of tailings against the liquefaction phenomenon. Several studies have shown that the level of confining pressure affects the cyclic resistance of sands, proposing the correction factor Κσ. Similarly, it has been observed that the initial static shear stress also affects the cyclic strength, so the correction factor Κα has been  introduced. However, the coupled effect of both variables, which corresponds to the real ground condition, has not been properly investigated for tailings sands. By means of undrained cyclic triaxial tests consolidated both isotropically and anisotropically, in this work the joint effect of both variables on the cyclic resistance of this material has been studied, for different levels of initial relative density. The results obtained from the coupled effect have been condensed through the parameter Κσα.