Analysis And Research On The Cable-stayed Suspension System And Construction Technology Of Long-span Concrete Box Arch Bridge

Since the 21st century,reinforced concrete arch Bridges are favored by bridge engineers because of their convenient materials and strong spanning ability,and have been widely used in the field of bridge construction.Considering construction safety,economy and other factors,the choice of construction method has become one of the first questions for engineers.The cable-stayed suspension method not only has relative advantages in construction cost,construction period and environmental protection,but also can deal with those unfavorable factors,such as steep canyons and rapid-flowing rivers.Therefore,it has a broad development prospect in the field of bridge engineering in China.In this paper,Niulu river bridge is taken as the engineering background,which is a deck type reinforced concrete arch bridge,and the length is 195 meters.In view of the large span of the bridge,the complex site and the large lifting weight of the arch box and other actual conditions,in order to ensure the safe and smooth closure of its main arch ring,this paper will carry out a specific study on the construction technology adopted by the bridge.The main work includes(1)Review the development history of reinforced concrete arch Bridges at home and abroad,and analyze the development status,advantages and disadvantages of various construction methods combined with typical bridge construction examples.(2)Summarize the current methods of cable force simulation and calculation,and make a comparative analysis of their application scope,advantages and disadvantages on the basis of defining their respective concepts.(3)In this study,finite element software BRanalysis and Midas/Civil were used to analyze the construction process of arch box hoisting,improved zero displacement method and elastic-rigidity struct method are used to calculate and compare the cable forces,then the unknown load coefficient method in Midas/Civil was used to optimize the cable force of the arch box of Niulu river bridge in each hoisting stage.So that the optimized cable force,the section stress and the linear shape of the loose cable can meet the construction requirements.(4)For the problems of the number of buckles,the angle of buckles and the timing of sealing hinge of arch feet,this study determined a reasonable scheme to guide the actual construction by comparing the size of the section stress,the stability and the linear shape of the loose cable in the construction of main arch ring under different schemes.