Mechanical Behavior Analysis Of Girder Of Long-span Cable-stayed Bridge

As an old type of bridge structure, the cable-stayed bridge has come out more than 200 years. But the rapid development and widely used of cable-stayed bridge is from the beginning of the 1970s. In less than half a century, the cable-stayed bridge spreads rapidly in the world. Advances in structural analysis, development of high-strength materials and construction methods have played a key role for the development of long-span cable-stayed bridge. With rich design experience and the use of advanced technology, the span length of cable-stayed bridge constantly refreshes the world record.The paper is under the background of the semi-float concrete cable-stayed bridge of Shuiyang river, following by some different aspects of research below:1. Analyzing the overall mechanical performance within the help of MIDAS Civil, thus helping to judge the bad mechanical performance situation. Then compare the girder internal force and stress of maximum single cantilever situation with the post situation. Finally the law of variation of internal force and stress of semi-float cable-stayed bridge during the system conversion is concluded.2. Based on the overall analysis, using the MIDAS FEA software to analyze the local mechanical performance of girder cross section.On the situation of maximum single cantilever, the positive stress distribution and shear lag coefficient variation of girder are studied under the combination of gravity, longitudinal pre-stress and cable stress. Following by the research:the influence of transverse pre-stress to the positive stress and shear lag coefficient of the girder.3. Taking account of the width of girder getting larger, which leads to the more obvious effect of transverse mechanical performance, thus makes it necessary to do the transverse local analysis of the bridge. Drawing the conclusion of the variation of girder transverse stress by comparing the transverse stress of the bridge under the combination of gravity, longitudinal pre-stress, cable stress and transverse pre-stress, can be a reference of the design of transverse pre-stress as well as the construction of girder.