Steel And Concrete Composite Continuous Beam Performance Study

Steel and concrete composite girder bridge structure can make full use of the material properties of steel and concrete.With reasonable force,strong applicability and beautiful appearance,it's widely used in city bridge design gradually.However,with the use of steel and concrete composite continuous girder bridge,the formulating reasonable design size and negative moment area concrete slab crack problem gradually revealed.Based on summarizing the existing research situation at home and abroad,this paper introduces the analysis theory of composite structure,and in view of the engineering example to carry on the design parameter analysis,research pivot jack-up method for combination of reasonable stress state in the hogging moment region of continuous girder bridges.This paper main research content is as follows:(1)Introduce the basic concept of composite structure bridge and classification,expound its development course,summarize the research status of domestic and foreign scholars for composite structure bridge,and analyze the factors that influence the combination structure bridge stress points out the present problems existing in the composite structure bridge.(2)Analyze the mechanical characteristics of steel and concrete composite girder bridge structure,introduce the method of elastic analysis and the plastic analysis method,and the difference between a failure criterion,two different cross section,and summarize the two cross section analysis theory as the method,the mechanics of the ultimate bearing capacity and the stress and the calculation formula of ultimate bearing capacity.(3)Set up the finite element model of steel and concrete composite continuous girder bridge,calculate and analyze of steel girder plate thickness,web plate thickness,the height of the web and other factors on the influence of the structure.(4)Summarize the improvement of the existing steel and concrete composite continuous girder bridges hogging moment area concrete slab stress method,analyze the fulcrum jack-up method for composite continuous beam stress in the negative moment region,research the influence of different jack-up displacement,and the effect of different jack-up order,and provide the direction of the optimum construction method of continuous beam combination.