The Analysis Of Progressive Collapse Theory For Base Isolations

In recent years, the earthquake disaster occurred frequently all over the world. Progressive collapse has become a major form of structural damage in the earthquake disaster. The related research on progressive collapse has begun since the collapse of the Ronan Point Tower in United Kingdom in1968at home and abroad, and developed relevant design codes and design guides. The paper use base isolation method in the study of resistance to progressive collapse with the following aspects of the work.(1).Summarized the norms and standards about domestic and international anti-continuity of the collapse, and researched the performance of structural anti-progressive collapse. Then, expounded theory as well as method in the design of anti-collapse at home and abroad, after that analyzed the impact of the progressive collapse of the main factors, and explored the mechanism of the structure collapsed.(2).Established a reasonable model for static analysis, and taken specimens of two cross-frameworks for analysis of internal forces. Then, calculated the isolation bearing three cases about a complete specimens of framework, specimens of a framework wiped off column, and one specimens of the framework wiped off column but plus the column end moment. The results showed that specimens of a frame plus isolation bearing, it had moment of column minimum value under equivalent static, and it had a stronger resistance to the collapse of superiority.(3).Established a common frame structure and the finite element model of the isolation frame structure by SAP2000, and taken a museum for instance, it had an anti-collapse dynamical computation of the framework structure. Used components removal of the law in two structures, removing the corner post, the middle column, long side of the column and the short side of column, then calculated and compared the internal forces and the displacement variation with the general framework and the base isolation framework. Analysis showed that removed a shorter post; the stress concentration zone appeared to the beam intersection in the remaining structure, and the common framework to post-column structural beams DCR values were greater than1which will be a continuity of collapse, but wiped off the column witch base isolated structure to specify the beam DCR values were mostly less than a progressive collapse does not occur.Finally, summarized the content and the main conclusions of the whole paper and give advice of the further study.