Time-history analysis & anti-collapse construction of storey-adding out-jacketing frame cooperated with the existing structure

To ensure the anti-collapse capacity of the storey-adding out-jacketing frame cooperated with the existing structure, time-history analysis by IDARC(2D) on the out-jacketing frame under rear earthquake are carried out, which shows that the lateral stiffness of the frame is quite weak below the adding structure; the damages of the existing structure is more serious than the one of the adding structure; and some of the out-jacketing frame designed by Code for design of concrete structures (GB50010-2002) & Code for seismic design of buildings (GB50011-2002) collapse under rear earthquake. Based on the analysis, application limits, column axial compression ratio limits, end-column moment magnification factors and construction measure of the out-jacketing frame are presented. Time-history analysis shows that by these reinforcing measures, collapse of the out-jacketing frame can be prevented effectively.