Local buckling of slender reinforced concrete structural elements by finite element method.

摘要

A plasticity based concrete constitutive model has been developed to study the local buckling of reinforced concrete structural elements. The concrete was assumed to be an initially isotropic and homogeneous material. Drucker-Prager failure criterion was used for compressive failure while Mohr-Coulomb failure criterion was used for tensile failure. Isotropic hardening and associated flow rules were used to model the response of the concrete between the initial yield state and the failure state. The smeared reinforcing model was used for the reinforcement (rebar) in the concrete. The rebar was assumed to be an elastic perfectly plastic material. The effects associated with the concrete and rebar interface were modeled through the use of 'tension stiffening' to simulate the load transfer across cracks through the rebar. This material model was implemented through a finite element code ABAQUS, Version 4.9.; The concrete constitutive model together with the finite element method were verified by analyzing and comparing with two series of tests. The comparison showed that the finite element method with proposed material model can adequately predict the local buckling of the reinforced concrete member.; Finally, an extensive parametric study for rectangular reinforced concrete panels supported along all the edges and subjected to in-plane compressive loading was conducted. The parameters considered included the concrete compressive strength, the reinforcement ratio, the panel aspect ratio, the panel slenderness ratio, and the panel boundary condition. The effects of these parameters on the load-carrying capacity of the panels were investigated. Family curves of buckling and post-buckling loads were obtained.