Estudo numérico de um dispositivo de transferência de cargas em pilares mistos tubulares preenchidos com concreto

Abstract

In Brazil, Standard Draft for design of steel and composite structures of steel and concrete with tubular, circular and rectangular profiles (PN 02 125.03-004) is on its final stages of development. This work aims at providing a numerical study of the device, which uses high strenght bolts, as elements of load transfer in composite columns of tubular steel and concrete, verifying the interaction between the steel tube and concrete core under a load applied directly on steel. For this study, was developed a numerical model for nonlinear geometric and material analysis using the Finite Element Method (FEM), with the commercial finite element program ABAQUS. Material and geometric properties of steel and concrete in the analysis were considered. To develop the numerical model, solid finite elements for steel and concrete parts were used, and also the contact between the parties were considered. A parametric study was conducted in order to verify an analytical model presented by Brazilian Draft Standard for design of tubular steel and composite structures, PN 02 125.03-004. The numerical results were compared with the analytical strength capacity obtained by the PN 02 125.03-004, which proved conservative. It was also observed that the stiffness of the bolts acting as the connectors are lower than the stiffness of the usual connectors as stud bolts. This way, it presents a multiplication factor of the number of connectors in order to maintain the stiffness of the usual connectors.