Construction And Dynamic Analysis Of Long-span Corrugated Steel Web PC Composite Box Girder Bridge

Since 2005 the first composite box girder bridge with corrugated steel webs was completed in China,the new type of steel-concrete composite beam bridge is widely used and promoted in China for the purpose of consume capacity and boost domestic demand,and its application scope is gradually expanding towards variable-span large-span beam bridges.According to the structural characteristics and experience gained from actual construction,a new asynchronous pouring construction method—RW construction method was proposed.Actually,the research on box-shaped bridges with corrugated steel webs is mostly concentrated on shear,bending,torsion and stability.In addition,model tests mainly focus on the small-span category of simply-supported beams rather than long-span bridges,the study on dynamic performance of long-span bridges is especially insufficiently.For the safe use and promotion of this structure,further research on its mechanical properties is needed.In this paper,the research was focoused on a PC combination continuous box girder bridge with a corrugated steel web of 85 + 9 × 150 + 85 meters in span.The specific force analysis of RW construction method and dynamic response analysis under earthquake are carried out as follows:(1)The finite element software Midas / Civil was used to perform a full-bridge simulation of a Yellow River Bridge.By dividing the corresponding construction phases,the new asynchronous pouring construction method—RW was simulated,and the static calculation is performed under the limit load condition.(2)A corresponding finite element model was established based on the cantilever construction process of the traditional corrugated steel web bridge.Compared the deformation and stress of this model with the model of the RW construction method,the difference of the two methods were obtained.(3)On this basis,the bridge substructure was simulated,a piled model A and a pileless model B were established,the effect of structure under pile-soil action was analyzed,and the response spectrum and time history analysis are performed to study the influence of dynamic characteristics on the bridge.(4)In order to research the effect of ground motion on long-span spatial structure,the traveling wave effect in multi-point excitation was used in this model.Dynamic response analysis was performed by loading three seismic waves along the longitudinal bridge,the seismic wave with the most influence was selected to analyze the traveling wave effect of the unidirectional propagation of the seismic wave.The conclusions derived from the research can provide a reference for the construction and design of the same type bridges.