Seismic performance and damping effect analysis of steel frame structure with shock absorbing staircase

• 1、Beijing Key Lab of Earthquake Engineering and Structural Retrofit, Beijing University of Technology, Beijing 100124

Abstract：In order to study the seismic performance and damping effect of the stairs with shear damping bearings, a 1/2 scale single staircase test model was designed and manufactured.Low cyclic tests were carried out on the stairs with shock absorbers, sliding bearings and fixed bearings under the action of constant axial force.The failure modes, hysteretic behavior, bearing capacity, energy dissipation performance and deformation capacity of different staircases are investigated. The damping effect of steel frame structures with three staircases is analyzed by using finite element software SAP2000. The results show that the hysteretic curves of the damping stairs are fuller, and the stiffness degradation is obvious, and the deformation capacity of the structure is stronger than that of the stairs with fixed and sliding supports.The horizontal relative displacement of the shear damping bearing is larger, which is beneficial to the damper. The vertical relative displacement can be neglected. The vertical stiffness effectively controls the pedal heave.The damping staircase can provide a higher additional damping ratio for the structure and improve the seismic energy dissipation capacity of the whole structure.

Keywords： Steel frame structure shock absorbing staircase pseudo static test seismic performance