Research On The Construction Technology Of Cantilever Casting With Buckle Cable System Based On The Main Arch Of Yelanghu Bridge

In recent years,the long span reinforced concrete arch bridge has been developed rapidly in our country.Arch rib construction methods mainly include: cast in-situ method,cable crane-assembly method,stiff skeleton method,swing method and cantilever erection method.Cantilever casting method was frequently used in the construction of arch bridge in abroad,Auxiliary Pier is arranged in the span,it not only reduce the cantilever length,but also reducing the construction difficulty,and decreasing requirements to the hanging buckle system,construction control was more easily.But at present,the using cantilever casting method arch bridges are only five,these span is relatively short and the cantilever casting using temporary piers has not yet been studied,so the lack of exploration on the construction of long span concrete arch bridge mechanical behavior.Therefore,taking the yelanghu bridge as the engineering background,around the cantilever casting with temporary piers carries out the following research:(1)On the basis of collecting the design data of the arch bridge with cantilever casting using temporary piers,the overall design of the construction scheme of the cantilever casting with temporary piers is put forward.the influencing factors of the location of temporary pier and determination method were analyzed,prestressed cast-in-place method is applied to arch cantilever casting construction,zero moment method is applied to the prestressed reinforcement calculation,and finally the analytical formula for calculation of arch rib prestressed tendons was deduced.(2)The mechanical behavior of arch rib in the construction of cantilever casting method with temporary piers was studied,and the influence of the tower and the prestressing tendons to the arch rib was studied.The influences of different arrangement forms of the fastening cable on the arch rib construction process and the arch forming state are analyzed.(3)In order to reduce the construction process of the control error,to carry out the sensitivity parameter analysis of mechanical effects on the construction process of the bridge,and the removal procedure of buckle cable after closuring arch was studied.