Abstract:Due to the inclusion of shear slip effect within the cracks and the consideration of both the fixed crack model and the
rotating crack model, the disturbed stress field model (DSFM) can more realistically simulate the shear behavior of the reinforced
concrete members. With the aid of the secondary development interface provided by the finite element software ABAQUS, a user material
subroutine (UMAT) is developed for the DSFM. The algorithm of separating the shear slip strain from the total strain was particularly
described, and then, the programming flowchart and method for the development of UMAT were introduced. The responses of reinforced
concrete panels tested in the University of Toronto were analyzed using the developed UMAT subroutine for DSFM and the built-in concrete
damage plasticity model of ABAQUS (CDP). The comparison results show that the developed UMAT subroutine can precisely predict the
behavior of the RC elements with different reinforcement and different loading conditions, while the built-in CDP model of ABAQUS can’t
be used to analyze the shear behavior of RC members, since it is incapable of reflecting the shear-stiffening effect after the
occurrence of shear cracks in RC elements.