Analysis And Research On The Stability Of The Cable-stayed Buckle-hanging Construction Of A Large-span Reinforced Concrete Arch Bridge

With the widely use of high performance materials in bridge structure,the spanning capability of bridge is stronger.As far as reinforced concrete arch bridge is concerned,the maximum span is 445 m.In the future,this span will be surpassed again.The design and calculation theory of arch bridge are relatively mature,so there is no much difficulty in the design of long span arch bridge,but which construction method is used to build the arch bridge is the primary problem that the engineers need to solve.At present,the steel-frame construction method is used mostly to build the reinforced concrete arch bridge which the span is over 300 m in China.But there are few problems with this method,such as using a large amount of steel,process complex and longer construction period.So,it will have great economic value for developing other construction methods on the 300 m span arch bridge.In this paper,the cable hoisting construction method of the arch bridge is taken as an object,the method application on the reinforced concrete arch bridge of 300 m span is studied.The stability in the construction process is analyzed,and the static stability of the hosting arch rib and the influence factors of the wind-instability are analyzed quantitatively.The main contents of this paper are as follows:(1)The application of cable hosting construction method on 300 m span reinforced concrete bridge was calculated.The results showed the method can fulfill the requirements of stress and construction control.(2)Construction stability and its influence factors of 300 m span arch bridge cable-stayed arch ribs were analyzed quantitatively.The factors include arch axis coefficient,ratio of rise to span,manufacturing defects,temperature load,cable restrain,Link stiffness etc.(3)Wind-static instability of cable-stayed arch ribs of long span arch bridges was analyzed.The aerodynamic parameters of three different span bridges were calculated by using the CFD modular of Midas/FEA.Through static loading,the wind-induced static instability analysis was carried out,and the influence factors were discussed.The results showed that the wind induced static instability was more likely to occur during the construction of the 300 m span arch bridge and static stability of the arch rib could be improved by increasing the cable force of the wave wind cables.