Modelling of reinforced-concrete structures providing crack-spacing based on X-FEM, ED-FEM and novel operator split solution procedure

摘要

In this work, we present a novel approach to the finite element modelling of reinforced-concrete (RC) structures that provides the details of the constitutive behavior of each constituent (concrete, steel and bond-slip), while keeping formally the same appearance as the classical finite element model. Each component constitutive behavior can be brought to fully non-linear range, where we can consider cracking (or localized failure) of concrete, the plastic yielding and failure of steel bars and bond-slip at concrete steel interface accounting for confining pressure effects. The standard finite element code architecture is preserved by using embedded discontinuity (ED-FEM) and extended (X-FEM) finite element strain representation for concrete and slip, respectively, along with the operator split solution method that separates the problem into computing the deformations of RC (with frozen slip) and the current value of the bond-slip. Several numerical examples are presented in order to illustrate very satisfying performance of the proposed methodology.