Chapter 3 - The investigation of the structural performance of the hybrid composite precast frames with mechanical joints based on nonlinear finite element analysis

Abstract

The structural behavior of the hybrid composite precast frames with the mechanical joints was numerically understood based on a nonlinear finite element analysis (FEA) considering the damaged concrete plasticity. The plastic behavior of concrete and the plastic part of the strain are estimated based on the plastic potential energy (flow rule). The degradation of the elastic stiffness of concrete is significantly different between tension and compression, the effect of which becomes more pronounced as the plastic strain increases. The failure mode and strain data observed in the experiment suggest the use of damaged the plasticity model with a confined stress-strain relationship in the region where the concrete degradation is expected. The flexural capacity of the connection plates for the precast components of reinforced concrete or steel-concrete hybrid composite columns is effectively increased by the internal stiffeners of the joint plates. The mechanical joint implemented in the precast concrete based moment-resisting connections with the concrete filler plates provides assembly speed similar to that of a steel frame and the flexural capacity similar to that of the mechanical joints with the steel filler plates. The experimental and numerical investigation verified the structural performance of the proposed hybrid frames with acceptable structural strength.