Life prediction of a self-propelled steel bridge based on co-analysis technology of finite element and fatigue simulation

摘要

Based on co-analysis technology of finite element and fatigue simulation, a methodology for life prediction of a self-propelled steel bridge (SPSB), is presented in this paper. Based on this strategy, stresses of critical-components and its risk-nodes in the SPSB, according to its actual loads and working conditions, are firstly identified through the finite element analysis. Then the load spectrum of every risk-node is generated and simplified by imitating movable load and integrating stress of the risk-node with time. And using the quasi-static method, stress-time history of every risk-node is also obtained. Finally, by modifying material S-N curve of the SPSB, simplified load spectrums of risk nodes and setting simulation parameters in MSC.FATIGUE, the shortest fatigue life of the SPSB is estimated using nominal stress method. The result of analysis shows that the life of the SPSB is about 34.2 kilometres, which is close to the expected life in design but more conservative.