The Study Of Design Method And Mechanism For Resisting Progressive Collapse Of Rc Frame Structure

Currently, the progressive collapse of the structures has become a serious threat to the public safety.Since the collapse of the Ronan Point Tower in United Kingdom in 1968, North America and Europe have researched on this issue for more than 30 years and developed relevant design codes and design guides,such as GSA 2003 and DoD2005.However,codes in China have not yet proposed in detail on the resistance of progressive collapse.This paper is mainly to the study of design method and mechanism for resisting progressive collapse of RC frame structures.Hence,based on the design process proposed in DoD2005 and the structural finite element analysis software SAP2000,the capacity to resist progressive collapse of a typical 4-story,6-story and 8-story reinforced concrete frame is analyzed.The main contents of this paper are as follows:1. Study the mechanism of progressive collapse according to the co-relationl studies in the world.Analyses the influence of structural components,structural systems and the action of abnormal loads on progressive collapse.The major conclusion is that the technology used to improve the ductility,robustness and redundancy in seismic design can also improve the ability to mitigate progressive collapse.2. A 4-story reinforced concrete frame building with the failure of long side column designed according to the current design code is analyzed using the finite element analysis software SAP2000 through four analytical methods,including liner-elastic static,nonlinear static,linear-elastic dynamic and nonlinear dynamic methodologies.Each method is thoroughly investigated and common shortcoming are identified,along with advantages and disadvantages.3. The 4-story,6-story and 8-story reinforced concrete frame buildings with the removal of coner column, side column and middle column are analyzed respectively using liner-elastic static alternative path-method. Analysing the internal forces and deformation and calculating the Demand Capicity Ratio (DCR) and displacement ratio after the removal of the critical elements.Then, comparison and evaluation the collapse resistant capacity of the structural.