Study And Inspection Of Axis Of Three-center Circular Arch Of Small-span Arch Bridge Under Special Geological Conditions

Arch bridge is a bridge with long history and beautiful curves.The traditional arch bridge generate a thrust to the foundations,and the value of the thrust increases with the span.For scenic spots or industrial parks with soft soil foundations,the thrust of traditional arch bridge limits its application,therefore,it is crucial to reduce the requirements of the superstructure to the foundation deformation.This paper focus on three center arc arch bridge,the finite element analysis software is applied to optimize the arch axis,and two three center arc arch bridges are analyzed considering the pile-soil action,and it is of great significance for the application of this kind of bridge,.The main contents include: 1.The axis equations of the three-center circular arc are proposed,and the parametric analysis of the center arch angle,the cross-span ratio and the middle arch radius of the middle arch are performed.The static characteristics of the structure under different design parameters are compared and the arches with different sagittal cross ratios are obtained.At the same time,from the perspective of structural stability,a reasonable ratio of the spans is obtained.2.Taking a single-span three-convex circular arch bridge and a two-span three-concentric circular arc arch bridge as background,the effects of two modeling methods that consider the joint action of pile-soil and do not consider pile-soil interaction are analyzed,which provides modeling suggestions for similar structures.3.The finite element software ANSYS was used to optimize the design parameters of the three-circle arc arch,and the vector height and center arch central angle were used as design variables.Three different optimization objective functions were used and the results are compared.Corresponding optimization solution provides theoretical guidance for the design of triple arc bridge.4.After the routine inspection of the bridge,and the actual working condition of the bridge is clear.Through the inspection,the consistency between the actual effect of bridge and the design conclusion is determined,which provides the corresponding technical basis for the later operation and maintenance of bridges.