Research Of Key Points In Construction Control Of Cable-stayed Bridge With Double Arch Tower

With its beautiful style,economical efficiency,etc,single-tower cable-stayed bridge has been applied more and more extensively,and the bridge style is designed more and more aestheticer by bridge designers.At the same time,the higher construction techniques and advanced construction controls methods are required.In this paper,taking the engineering of Xiaolinghe bridge as example,three key points are studies of construction controls techniques in double arch-tower cable-stayed bridge.The main investigations are as follows.(1) The force of flexible cable of cable-stayed bridge is studied in combination analytical method with nonlinear FEM.Based on the generalized impact matrix concept,the target state of the cable-stayed bridge which needs to be controled and adjusted,is represented by the cable force and impact matrix.With constant non-stress length,the force of flexible cable is iterative calculated.(2) The construction control technology of the beam-drop method for long-span steel cable-stayed bridge is investigated in this paper.According to construction requirements of large extent beam-drop for Xiaolinghe bridge,choosing sand box as temporary piers, beam-drop is implemented by multi-step classification method.Take the security of each temporary pier,the stress and deformation of steel box beam as control criterion,the entire construction process of sand box beam-drop method is established by numerical methods,to define the step number of beam-drop and drop distance of each step.(3) To analyze the the construction process,the three-dimensional space FEM model of arch-tower vertical rotation is established to calculate cable force,arch tower force and displacement under different angles.To ensure the security of arch tower throughout the construction process.