Abstract:Based on the theory of anisotropic elastoplasticity, a nonlinear anisotropic constitutive model for PVC coated fabric membrane was proposed. It is based on the inherent nonlinearity of material represented by equivalent stress and equivalent plastic strain, and combined with the three parameter elastoplastic yield function. In order to determine the parameters of the constitutive model and to verify the applicability of the model, uniaxial tensile tests in 7 off axial directions(0°,5°,15°,45°,75°,85° and 90°) were carried out. By comparing the predicted results of the model with the tensile test results, it is found that the constitutive model can accurately reflect the non linear stress strain relationship of the PVC coated fabric membrane. It can be used to predict the mechanical behavior of the PVC coated fabric membrane under the combined action of tension and shear stress.