Secondary development and application of unified elastoplastic constitutive model to ABAQUS

Based on finite element theoretical scheme of unified elastoplastic constitutive model,and according to the UMAT interface requirement of ABAQUS,the corresponding UMAT codes are programmed,which will be called by the main analytical module of ABAQUS.Adopting degenerative model of the unified strength(b=0,Mohr-Coulomb model) and the built-in Mohr-Coulomb model of ABAQUS,the uniaxial tests and circular chamber are analyzed to verify the correctness and efficiency of the developed material subroutine.Finally,considering the general situation form of unified elastoplastic constitutive model(b ≠ 0) and hard condition of yield surface,which are not available in ABAQUS software,circular chamber is simulated and variational discipline of stress field is obtained.The provided basic procedures and programming essentials of the UMAT redefining in ABAQUS are universal and can offer a reference for other developers.