Abstract: Normalized stress ratio ? is defined relate d to stress turning angle á . Bas ed on the disturbed state concept and hypoplasticity theory, the elasto-plasti c and damage model is developed by means of the method from simple loading to comp lex loading. The model could be used to describe the strength and deformation c har acteristic of structured soils under simple and complex loading. The correspondi ng elasto-plastic and damage matrix is derived so that the model can be implem ented into finite element code.