Damage distribution mechanism of common low-rise steel frame structures

Abstract

In order to research the damage distribution mechanism of common low-rise steel frame structures under dynamic action, this paper took the column-to-beam strength ratio αi and column base form as the main parameters to research the seismic performance of common low-rise steel frames. To achieve this goal, 24 models of common low-rise steel frame structures were designed and analyzed by elasto-plastic time history analysis method; and the predominant periods of seismic waves are similar to the fundamental periods of these models. This paper focuses on the demand performance of each model such as the distribution of maximum inter-story drift ratio (MIDR), the deformation concentration rate of the first floor dR1, the ductility ratio μ and cumulative plastic ductility ratio η of the beams and columns; and clarifies the relationship between the damage mechanism of common low-rise steel frame structures and column-beam strength ratio αi and column base form in the first place. After that, to investigate the effect of each parameter on the structural energy dissipation, the plastic deformation energy distribution of each model was also studied in this paper. Finally, the mathematical equations of the seismic input energy and plastic deformation energy were studied, which can apply to common low-rise steel frame structures in the resonant state. It can provide a reference for engineers to choose the column-to-beam strength ratio αi and the column base form in the design of low-rise steel frame structures.