Seismic Design For Multi-Story Steel Frames Composed Of Slender Or Non-compact Section

Being more expanded, slender sections are of larger moment-resisting capacity and better structural stability than compact sections. So the economy of applying the slender sections to structures is significant. The slender steel frames, that will be studied here, are of slender sections of H shape. However, problems are parallel to the economy: element sections are liable to local buckling for the member's large width-to-thickness. The problem of sections leads to problem of structures: low ductility, reduced yield capacity, shrunken energy-absorbing ability. Just for those deteriorated characters, the slender steel frames are excluded by actual seismic code in China.With the rapid development of multi-story steel dwelling houses, multi-story slender steel frames have been widely used. However, the seismic code restricted the application of slender steel frames greatly; furthermore, the deteriorated characters of such frames threaten the structural safety severely. So, to assure the structural safety while slender steel frames are applied at seismic zones, it is necessary to investigate their seismic performance and to put forward seismic design method for slender steel frames. The dissertation is to solve this problem to a certain extent.The dissertation commences with the investigation of slender sections. The notation of "buckling hinge", which is different from "plastic hinge", is firstly presented. In order to get more extensive conclusion, both the plastic hinges and the buckling hinges are investigated while the plastic hinges being classified as one category of buckling hinge. Five hundred elements are analyzed by program JULIET (a nonlinear statistic analysis program), each element producing one curve of moment-rotation. Based on the analysis of all those moment-rotation curves, the curves are classified to three categories and regression formulae are presented according to each category. The reliability of program JULIET is affirmed through testing data and finite element analysis data before applied largely. And the accuracy...