Reliability Analysis Of Composite Space Truss

Composite space truss (CST) is a kind of space structure composed of steel tubes and reinforced concrete ribbed slabs. It is full of steel in tension and concrete in compression favorable conditions for the strength of two different materials to play their respective advantages, also can make the structure's load-bearing and surrounding functions come into integrity. Over recent years it has developed a structured form of the future.The research of the structure is mainly in elasticity at home. The yield mechanism and the failure mode of the CST are not well understood.Compared with the concrete structure and steel structure, study on the combination of redundant structure grid reliability was not thorough enough, so, the research is significant. The current design theory are targeted to components,it can only guarantee on behalf of the state of the reliability of the ultimate load level, while the whole structure can not guarantee the reliability limit state load level. In this paper, based on a combination of ultimate bearing state grid reliability analysis is based on nonlinear analysis and the whole structure checking, it can ensure the reliability of the whole structure rather than the component level, so this research has important theoretical significance and engineering applications.This paper including the following:Firstly, this article makes the systematical nonlinear finite elements analysis about CST. Finite element model involving geometric large deformation and materials nonlinear are presented, which has been carried out to simulate the ultimate behaviour of the simply supported CST with the aide of program of ANSYS.Secondly,based on basie theory of struetural reliability and ealeulation method,using basiec conception of struetural reliability,ultimate state and relationships between struetural reliability and failure probability and applying Monte-carlo method,and bearing eapaeity limiting state reliability analysis of simply support composite space truss is carried out using Monte-carlo method.Through the tracking of structural damage process, obtained the the limit load, and given a clear pattern of structural damage. Through the combination of ultimate bearing based on the whole network reliability analysis, obtained the approximate range of structural reliability, structural reliability analysis of a greater impact on the sensitivity of the parameters, given the possible measures to improve the structural reliability.By making the analysis of CST elastic and plastic buckling strength, it was hoped that this paper can put forward some reference suggestions for the study of CST.