Sensitivity Analysis of Seismic Behavior of Steel Structures for the Plastic Hinge Parameters

Nonlinear behavior of structures in push-over or time-history analyses is normally considered through defining plastic hinges at two ends of each element. A sensitivity analysis is carried out here on the influence of each parameter of the plastic hinges on the overall seismic behavior of the building. For this, PERFORM-3D was applied for the analyses. Two structures, with one and two stories, were pushed over and analyzed under five earthquake records as well. The obtained results show that base shears of the assumed structures depend on their own lateral strengths rather than the record properties. Furthermore, Idealization of the hinge behavior with bilinear curve can severely affect the results of the base shear and storey drifts. It is also shown that raising the ductility increases the structural stability and therefore, special attention should be paid to the ductility rather than stiffness or strength, in order to have safe structures in earthquakes.