Study On Shear-lag Of Bridge Panel Combined With Girder Cable-stayed Bridge

The difference between the force of the bridge deck of the cable-stayed bridge and the bridge deck under the theoretical analysis of the elementary beam is the following two points.Firstly,due to the existence of the shear connection,the bridge deck of the cable-stayed bridge is synergistic with the steel main beam.Force,secondly,the tensile force of the cable causes the bridge deck at the anchor point to produce obvious uneven force,and the local uneven force increases the probability of local damage of the bridge deck.Therefore,in order to make the stress of the bridge deck of the cable-stayed bridge of the composite beam safe and controllable,it is imperative to analyze the space effect.Although many scholars at home and abroad have carried out multi-faceted analysis and research on the shear lag of the bridge-stayed bridges,many theories have been promoted to the understanding of the shear lag of bridge decks,but in the case of one bridge Other negligible factors affecting the shear lag of the bridge state,such as simulation,segmentation construction,temperature gradient,and live load considerations,are lacking.The construction process of the cable-stayed bridge is extremely complicated.The bridge stress is constantly changing under the control of various influencing factors,which may cause the internal force of a certain construction stage to exceed the internal force of the bridge state,and then replace the internal force of the full bridge.In order to avoid this situation,the shear lag effect of the construction process must be fully considered in the design of the cable-stayed bridge.The paper relies on the Minjiang River Bridge as the background project,combined with the research results of the predecessors,using MIDAS/FEA.The MIDAS/Civil is used to analyze the shear lag effect of the composite girder cable-stayed bridge and the construction stage.The following contents are studied:(1)Briefly expound the necessity of studying the shear lag effect of the bridge deck of the cable-stayed bridge,according to the characteristics of the composite cable-stayed bridge and the extraction of the shear lag effect.(2)Using the finite element software MIDAS/FEA to simulate the combined cable-stayed bridge and compare it with the MIDAS/Civil calculation results to ensure accuracy and provide shear-lag coefficient data preparation.(3)The engineering background is the Chongqing Weinan Hanjiang Bridge,whichis used to establish the linkage model of the cable-stayed bridge and the three-dimensional solid finite element model to explore the optimal coupling of concrete bridge deck,steel main beam,wet joint and stay cable.Simulation analysis method.(4)Study the state of falling bridge into a bridge,considering the bridge formation and temperature gradient in the construction stage,and the effect of live load on the shear lag effect of the bridge deck of the cable-stayed bridge.(5)Study the variation of shear lag of bridge decks at different construction stages,the longitudinal distribution of maximum cantilever shear lag coefficient,and the different formation modes of bridge decks(wet seams are cast at the current stage,wet joints are cast in one stage,and delayed Analysis of the effect of two stages of wet joints on shear lag.