Fatigue Life Analysis Of Weld Detail Of Steel Bridge Monolithic Joint

Along with the wider use of monolithic joint in the design of long span steel truss bridges, the fatigue of weld details under traffic loads gradually attracted more attention of the architects. However, because domestic fatigue research started relatively later than the national, so we are lack of valid methods to calculate the fatigue life the buildings. The primary purpose of the issue is to analyze the process, principle and calculating method of the fatigue damage calumniate with advanced analysis principles and instruments. The issue is based on the background of Tsing Ma Bridge, and put forward some effective and easy to operate methods solve the problem.Firstly, a number of basic concepts and the present status of the fatigue research are introduced, some fundamental principals such as S-N curves an Miner Rules are also addressed. The dominating means of fatigue analysis do have some weak points, so we select BS5400 and a professional fatigue soft "fe-safe" as the main method of the analysis.Secondly, the issue discussed various factors that may have an influence on the fatigue life of the members. Because of the particularity of weld fatigue, these factors have a different impact on the fatigue life of the members. So we emphasized the relatively rules in BS5400, and deeply considered the reason of these chooses, all of these is very helpful for us to use and comprehend the criterion.Lastly, we established the finite element mode of the truss joint of Tsing Ma Bridge on the base of the works of forerunners, defined boundary and loading conditions according with the reality, and proposed some new understandings of the finite element mode of weld details. With the results of stress calculation, we applied nominal stress and hot point stress to analyze the fatigue life. Finally, we compared the results of two method, and proved the accurate of these methods.