The Adaptability Analysis Of Straight Prestressed Concrete Beam With Simple Support Before Continuous Prestressed Concrete In Curved Beam Bridge

The current continuous curved beam bridge on a flat curve,when the plane curvature radius is large,the prefabricated straight beam body is usually used to approach the flat curve in multiple sections,and the outer cantilever end of the side beam changes in a circular arc.This design method is a curved continuous beam The bridge prefabrication assembly construction provides great convenience.Aiming at the design method of simply supporting and then continuous concrete girder bridges on a flat curve with a certain radius of curvature,the design department has formed a number of common practices,but the systematic and mature regulations have not been found in the bridge design specifications and design manuals.This paper studies the adaptable curvature radius and the adaptable bridge length of a curved bridge on a circular curve for a commonly-used30m-span prestressed concrete box girder bridge that is simply supported and continuous.The research results will provide references for engineering design.The main work of the paper is as follows:(1)Relying on the construction design drawings and material parameters of a certain project,a three-span prestressed concrete box girder bridge with a span of 30 m was constructed,which was simply supported and then continuously prestressed.The solid element finite element model and the grid method were limited by the curved bridge.The element model,through the vibration modal analysis and static force analysis,verifies the accuracy and validity of the beam grid method finite element model based on the mechanical feature modeling method.(2)with the aid of beam model,analyzed the league three straight across the curve continuous box girder bridge with curved bridge,when the radius of curvature is 500 m,600 m,700 m,800 m,900 m,1000 m,1100 m,1200 m under the different values,such as the maximum internal force of each control section girder with girder cross-section torsion limit bearing capacity checking of the curve beam bridge with curved bridge straight do to adapt to the radius of curvature is 500 m.(3)With the aid of the grid-girder method model,the change law of the deformation of the support,the torsion and the temperature effect of a three-span curved continuous girder bridge with a straight curved girder bridge is analyzed.(4)For a continuous bridge length respectively take 3 x 30 m,30 m4 x,5 x 30 m,6 x 30 m,by using the beam model is analyzed from a different bridge of long span box at the bottom of edge protection torque values change,the radius of curvature for 700 m and 800 m adaptation bridge for 4 across a long,at about 900 m radius of curvature of adapt to the bridge length of 5 span,curvature radius is greater than or equal to1000 m to adapt to the bridge length is 6.