Parameter Sensitivity Analysis And Research On Reasonable Construction State Of Four Tower PC Cable-stayed Bridge

With the development of transport construction, the multi-tower cable-stayed bridge has big spanning capacity and a good prospect of economic; they are used in practical engineering more and more. For cable-stayed bridge, in the case of reasonable state, the problem of how to determine the reasonable construction state must be first to think about in the construction control, the common cable-stayed bridge already had better solutions, but for multi-tower cable-stayed bridge, the mechanical characteristics are different from those common cable-stayed bridge, calculation methods of reasonable construction state have many questions remain to be further discussed. This paper use Chi Shi super-large Bridge as the engineering background, mainly discussed several work as following:1. According to multi-tower cable-stayed bridge mechanical characteristics, reasonably simulate the actual structure boundary conditions, think over the construction hanging basket structure and the influence of load on the bridge structure, simulate the actual construction condition, and establish Chi Shi super-large bridge construction process analysis and calculation model using the finite element method.2. Based on the least squares principle, using the influence matrix method combined with part of the manual adjustment line method, in accordance with the given reasonable bridge state, make the Bridge Girder Cable Force, Bending Moment, the Main Tower Offset as the goal, taking stress safety into account, the Chi Shi super-large bridge stay-cables initial tension of construction process is obtained, then the reasonable construction state is obtained; every middle tension of cable force and the vertical mold elevation of the main girder construction beam segment are determined on that basis, also determined the Chi Shi super-large bridge theory construction trajectory.3. Analyze some parameters that influence the construction process and the bridge state, for example, weight of beam, construction loads, structural stiffness, cable force, shrinkage and creep, temperature and so on. As a result, this simulation deduces the sensitivity of parameter for the four towers and high piers PC cable-stayed bridge structure.