Seismic Performance Analysis Of Steel Self-Centering Frames

The traditional steel frame can cause great residual deformation under earthquake action which would result in the permanent damage to the structure, bring great difficulties to the repairmen after earthquake, and cause great losses. The foreign and domestic scholars put forward a novel self-centering node to replace the tradition welded and semi-rigid nodes to offset the defect.The nodes only have local effects, which cannot reflect the mechanics characteristic of the integral structures. Therefore the main job of this paper is to apply the self-centering nodes into the steel frames. The ANSYS software is used to simulate the monolayer and multi-layer steel frame system, and then hysteretic behavior is studied under the cyclic load and seismic force. According to the hysteretic curves and time history results of displacement, we have summarized that the self-centering steel frames have the capacity to control the structural displacement response and reduce the residual deformation.Firstly, the quasi static analysis of monolayer self-centering steel frame system is performed by applying the cyclic load. Taking into account the complexity of simulating the beam, column and angle steel by solid element, COMBIN39element is used to simulate the contact among the beam, column and angle steel by set real constants and other parameters which greatly reduce the computation time of numerical simulation. The simulation results of self-centering and normal steel frames show that the self-centering steel frame has energy-dissipating and self-centering capacity. When applying different initial pre-stress to the pre-stressed steel strand, the self-centering capacity of self-centering steel frames increases with the increasing of initial pre-stress, and at the same times the stiffness and bearing capacity of the structure also have a corresponding enhancement. At last the contrastive analysis of self-centering and normal steel frames for monolayer and multi-layer is conducted subjected to earthquake, and the results show that the self-centering steel frame has the energy-dissipating capacity and the self-centering steel frame can control the maximum displacement and reduce the residual deformation meanwhile under earthquake.