Credibility of estimating the hysteretic energy demand of moment-resisting steel frames

Abstract

Seismic design is of high importance. The energy-based seismic design method, which features a clear conception, is beneficial to the comprehensive evaluation of structural seismic performance. However, how to determine the energy demand is fundamental. In this paper, moment-resisting steel frames were designed as calculation examples in accordance with the current specifications and standards in China. Then, such structures were subjected to the elastic-plastic time history analysis. The analysis results revealed that the hysteretic energy (HE) demand obtained via the time history analysis was smaller than the estimated value. Under different seismic waves, the inter-layer hysteretic energy demand of different structures presented identical distribution laws, and the proportion of the hysteretic energy in each component in the total hysteretic energy was also relatively stable. In addition, the energy dissipated on the intermediate floor of the moment-resisting frames was large. Under rare earthquakes, all components designed by the small earthquake elasticity design methods entered the plastic stage, with an uncontrollable yield mode. Therefore, it is rather essential to investigate energy-based design methods.