Feasibility Analysis Of Regional Confined Concrete In Reinforcement Of Arch Bridge

Based on the research results of regional confined concrete in building structures,this paper explores the feasibility of its application in arch bridge reinforcement.According to the research results of a large number of scholars,the regional confined concrete can be used for structural members such as compression,bending and torsion,and can better improve the mechanical properties of concrete members.In this paper,based on the reinforcement projects of two types of arch bridges,i.e.double arch bridge and truss arch bridge,the finite element analysis method is adopted to apply the regional constraint and ordinary reinforced concrete to the method of increasing the cross section of arch bridge for comparative analysis.The article first introduces the five stages of the development of arch bridges in our country and illustrates the important position of arch bridges in the history of bridges in our country.This paper lists the problems of exterior diseases and insufficient bearing capacity of some arch bridges,and expounds the necessity of strengthening the arch bridges.Different bridge reinforcement methods are introduced according to the structural form and stress state of the arch bridge.Based on literature review,the calculation theory of regional confined concrete compressive strength,the research status at home and abroad and the significance of this research are briefly described.Midas Civil finite element software is used to model and calculate the State Road 210 double arch bridge and Duyun truss arch bridge in Guizhou Province respectively,and the internal force of arch ribs under dead weight and vehicle load is obtained.Intercept the arch rib within 5m from the arch foot,and use Midas FEA finite element analysis software to carry out solid modeling.Linear elastic analysis,linear buckling analysis and static non-linear analysis are respectively carried out on the arch ribs of the double arch bridge in State Road210,Guizhou Province strengthened by the ordinary reinforced concrete increasing section method and the area confined concrete increasing section method.Static non-linear analysis is carried out on the arch ribs of Duyun truss arch bridge in Guizhou Province strengthened by the ordinary reinforced concrete increasing section method and the area confined concrete increasing section method.In the elastic stage,comparing the displacement,deformation and stress of the two reinforcement methods for the double arch bridge,it is found that the reinforcement effects ofthe two reinforcement methods are basically the same.In the plastic stage,for double arch bridge and truss arch bridge,compared with ordinary reinforced concrete,the regional confined concrete can reduce the tensile stress of the original bridge arch rib concrete,the tensile stress of stirrups in the reinforced arch rib concrete and the compressive stress of longitudinal reinforcement,and improve the compressive stress of the reinforced concrete of the arch rib.This is beneficial to the structure.The high compressive strength of the regional confined concrete is fully utilized,which proves that the regional confined concrete reinforcement of double arch bridge and truss arch bridge arch rib by increasing the cross section method is feasible to some extent.The analysis conclusion of this paper can be used for reference and reference in engineering.