Methods for establishing yield function of soils

Six methods for establishing the yield function of soils are summarized, and taking Cambridge Model and Modified Cambridge Model as examples, the approaches of the stress-dilatancy method and the thermodynamics method are explicated. The advantages and disadvantages of these methods are analyzed. It is found that the stress-dilatancy method , the plastic strain increment method and the thermodynamics method are the same in nature and all of the three methods need to establish yield functions from their “equivalents”. The forms of the “equivalents” are the equivalent relations of algebraic, geometrical and energy aspects, respectively. Finally using the sixth method, a shear yield criteria for coarse-grained soils is proposed based on the results of conventional triaxial and true triaxial tests on these soils.