Study On The Construction Technology Of Cable Hoisting Segments By Weight-transverse Movement Of CFST Arch Bridge

Cable hoisting system has the advantages of large lifting capacity,fast transportation and easy operation.It is especially suitable for the construction of arch bridge,cable-stayed bridge and suspension bridge on special terrain such as canyons and rivers.Most of the steel tube arch ribs of concrete filled steel tubular arch bridges built and under construction in China are constructed by cable hoisting and cantilever assembling method.Due to the limitation of the terrain conditions on both sides of the river,the integral cable hoisting system with suspension tower and cables that hold down the tower at the top of the steel tube arch rib and the construction technology of segments by weight-transverse movement are adopted in the installation of the steel tube arch rib of the Jiangkai River Bridge in Guizhou Province.In the integral cable hoisting system,the deformation and stress of the tower are complex in the construction process,and weight-transverse movement of segments further increases the complexity of the force of the tower.Influenced by the cables that hold down the tower at the top of the tower,weight-transverse movement will also cause the elevation change of the section with installed arch ribs,which raises new problems for the construction and construction control of steel tube arch ribs.For this reason,based on Guizhou Jiangkai River Bridge,this paper carries out research on the construction technology of cable hoisting segments by weight-transverse movement of concrete filled steel Tubular arch bridge:(1)The design of hoisting system for weight-transverse movement.The main cable,lifting cable,traction cable,tower and transverse system of cable hoisting system of Jiangkai River Bridge are designed.(2)Study on the mechanical behavior of integral tower frame in the process of weight-transverse movement.The spatial model of main arch,tower,cables that hold down the tower,rear cable wind buckles and anchor cable is established by using finite element program.The deviation,stress and stability of integral tower in the whole process of arch rib installation and weight-transverse movement are analyzed according to the construction scheme.(3)The linear effect of weight-transverse movement on the arch ribs of Jiangkai River Bridge.This paper studies the alignment change process of the installed arch rib segment in the course of transverse movement with weight and its influence on the alignment of the subsequent section to be installed,and puts forward the corresponding alignment control measures.(4)By comparing the lifting schemes before and after the adjustment of Jiangkai River Bridge,it is beneficial to improve the safety of arch rib hoisting construction after the completion of the installation of the third segment and lateral brace under the premise of strictly controlling the alignment of installation through theoretical calculation.(5)The alignment test of pylon and arch rib is carried out in the construction of arch rib hoisting of Jiangkai River Bridge.The measured data and theoretical values are compared to verify the feasibility of the construction technology of cable hoisting segments by weight-transverse movement.