Non-associated mechanical modelling of soft Finnish clays

This article deals with a non-associated mechanical model for soft clays. The aim of this study was to improve the accuracy of mechanical modeling of soft clays by defining and testing a non-associated flow rule. An inclined ellipse was used as a yield surface, and the focus was in the determination of plastic potential surface. The parameters of the model were derived from drained triaxial test results. The derived parameters of the model are presented for some Finnish soft clays. According to the comparison between observed and calculated values, the non-associated mechanical model performs fairly well. Clearly, the shapes of the yield surface and the plastic potential surface differ. However, the model should be further tested for different clays and other soils in order to verify the results. In addition, the plastic potential surface should be defined for extension as well.