1. Central South University of Forestry and Technology, College of Civil Engineering and Mechanics, Changsha 410004, China;
2. Hunan University, College of Civil Engineering, Changsha 410000, China
Based on theory of structural dynamics, two kinds of improved push-over analysis (POA) procedure are deduced to consider the vertical effect of near-fault earthquake. In improved methods, the vertical seismic force is loaded on every lumped mass before structural push-over analysis, and the lateral load distributions as well as the shape vector are modified according to the dynamical features of the structure after yielding. Applying two improved and two traditional POA procedures respectively, two frame structures on near-fault site, as numerical examples, are investigated for their important seismic response, such as the roof displacement, the floor displacement and the inter-story drift. According to the statistical results of structural dynamic time-history analysis based on 30 sets of near-fault ground motion records, the seismic response parameters estimated by different POA methods are testified for their precision. The results show that the modified methodⅡ possesses much higher precision compared with other methods, this method can simultaneously estimate the maximum roof-displacement, maximum floor-displacement and maximum inter-story drift of frame with high accuracy，hence can be applied to the seismic response analysis and seismic damage assessment of regular structures on the near-fault site.
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