Research On Establishing Method Of Fatigue Multiple-line Coefficient In Fatigue Design Of Long Span Railway Steel Bridge

With the development of society and the increasingly augment on carry capacity of railway, single-track line bridge and double-track line bridge will no longer satisfy the demand of develop. It is a trend to build multiple-track line bridge in the future. Fatigue problem is one of the key indexs to scale the bridge life, therefore the research on fatigue problem in multiple-track line bridge becomes important. The existed railway bridges in China are either single-track line bridges or double-track line bridges. Checking fatigue to double-track line steel bridge, we should take two trains possibly passing bridge at the same time into consideration, and fatigue make cumulated damage contain with this loading effect. Which is modified by double-line coefficient in the Code. The major content of this paper is to study a method to establish multiple-line coefficient. Started with analyzing the establishing method for double-line coefficient in the Code, finds that, based on the train service situation, the probability of train encounter on bridge should be analyzed frist so as to get the encounter times on the bridge, and then the double-line coefficient is obtained as a fatigue damage ratio between the effects of double-line loading and one track loading, according to the fatigue accumulated damage theory. Following the research route, this paper studys the establishing method to the fatigue revised coefficient for triple-track line bridge and quadruple-track line bridge, and then deduce the establishing coefficient method and step for any multiple-track line bridge.Tian Xingzhou Yangtse River bridge in construction in Wuhan with highway and railway combined, is an other long span cable-stayed bridge after Wuhu Yangtse River bridge. It should be emphasized that this bridge is the first bridge to have quadruple-track train load with two lines of heavy loads in the world. This paper, use STAAD/PRO design software to establish a three-dimensional structural model of Wuhu Yangtse River Bridge, and calibrate it by the test data in real bridge. After that, modeling Tian Xingzhou Bridge and compute. By the...