The Shrinkage And Creep Analysis Of Long-span Concrete Cable-stayed Bridges During Operations

Long-span concrete cable-stayed bridges are sensitive to shrinkage and creep. Large error with respect to the predication of shrinkage and creep would lead to some difficulty of realizing the actual operation of the bridges and lead to deterioration of serviceability problems, aesthetics and eventually early reconstruction of the bridges. This thesis mainly analyzed the influence of three long-span concrete cable-stayed bridges during the operations that arise from the effect of shrinkage and creep, tried to get the shrinkage and creep rules of the different types of long-span concrete cable-stayed bridges during the operations. The major content of this thesis are as follows:(1). This thesis assorted the familiar shrinkage and creep predication models abroad and home, detailedly compared the model of the new version China Standard of Highway PC Bridge (JTG D62-2004) with the model of the old version China Standard of Highway PC Bridge (JTJ023-85).(2). Using the analysis method of shrinkage and creep based on initial strain, This thesis fitted the shrink strain and the creep coefficient function with uniform exponential function model and find a way to get the recursion formulae of shrinkage and creep.(3). This thesis compared the academic calculation of shrinkage and creep based on design code with long time health monitoring data, verified the shrinkage and creep models in design code are adopted in analysis of actual long-span concrete cable-stayed bridges.(4). Based on the models of shrinkage and creep in design code and the limited element method, This thesis analyzed the influence of the different types of long-span concrete cable-stayed bridges during the operations which arise from the effect of shrinkage and creep, concluded a series of same and different rules.(5). This thesis derived the simple formula for the deflection of main girder which arise from the effect of shrinkage and creep, preferably explained the deformation and internal force regularity which arise from the effect of shrinkage and creep.