Seismic damage-based design of steel moment frames

Abstract

Since the seismic performance of a structure is different under different earthquakes, the extent of damage to different members of a structure will not be the same and the distribution of damage in different stories will vary. Experience from previous earthquakes has shown that damage is more severe on the first story than on other stories. Therefore, in the present study a new method has been developed, based on the Park-Ang damage index, to design steel moment frames, assuming elastic-perfectly plastic behavior (EPP) in these frames; this method can control damage to structures in earthquakes. To assess the performance of this method some structures were designed using the proposed method as well as some other methods, and then they were tested and compared under some earthquakes. The results show that this method can effectively overcome the weakness of lower stories and control the amount of damage to members, stories and the whole structure. The nonlinear dynamic analysis was carried out using OpenSees software, and the damage indices were calculated using the code written with MATLAB software.