INFLUENCE OF STEEL FIBERS AND AXIAL COMPRESSION RATIO ON MECHANICS BEHAVIOR OF PRESTRESSED WIDE-BEAM FRAME

Nonlinear finite element analysis was carried out to fiber-reinforced unbonded-prestressed wide-beam frames using the ABAQUS program, influence of steel fibers and axial compression ratio on mechanics behavior was discussed. The concrete damaged plasticity model was used during the analysis, contribution of steel fibers to nonlinear behavior of concrete is considered. Effects associated with the rebar/concrete interface were modeled as spring element to simulate the bond slip action. It was proved to be feasible to carry out the analysis using the materials and elements providing in ABAQUS program. The influences of steel fibers and axial compressing ratio on the mechanics behavior of prestressed wide-beam frame were investigated. The results show that the large axial compressing ratio can promote the ultimate loading capacity, but reduce the ductility and energy dissipation. Limitation on axial compressing ratio was advised for prestressed wide-beam frame in earthquake region. Steel fibers could effectively improve the ultimate loading capacity, ductility and energy dissipation, thus contributed to improving the seismic behavior of wide-beam frames. The effect of steel fibers is related with axial compressing ratio.