NONLINEAR SOIL MODELS FOR IRREGULAR CYCLIC LOADINGS

Current analytical and mechanical models for shear-stress shear-strain relationships under cyclic loading are described. These models generally comply with Masing's suggestion that unloading and reloading curves have the same shape as the initial loading curve except that they are enlarged by a factor of two. A new hypothesis is presented in which this scale factor is made a function of the stress level at the last reversal point. This new hypothesis leads to shear-stress shear-strain relationships under irregular cyclic loading that appear to give better agreement with experimental data than the existing models.