Self-anchored Suspension Bridges Key Construction Phases Analysis And Investigation

Self-anchored suspension bridge is an economic, rational and beautiful bridge. Self-anchored suspension bridge has been constructed more and more in our country in recent years, and is becoming more long in the span and large in the scope. It takes more new projects to design and construction. Based on Nanjing self-anchored suspension bridge, the detail as the following:(1) The calculate methods of the main cable shape were researched, based on different hypothesis, two methods were deduced, the parabola method of cable gravity distributing uniformly along the span, and the catenaries method of gravity distributing equally along the curve. Finite element analysis model was set up for iteratively calculation of the main cable shape and the unstressed length.(2) The exitent analysis theories of suspension bridge were summarized and compared in the paper (the theory of elasticity, the theory of deflection and the theory of finite displacement), the more advanced, high precision, more applicable theory of finite displacement was choosed, the tangent stiffness matrix of the beam elements, the link elements and the catenary elements were deduced.(3) The nonlinear influences of self-anchored suspension bridge were represented extraordinary overhang at construction phases. The material nonline, the geometric nonline and the contact nonline of suspension bridge were summarized, several commonly nonline equation calculate methods were discussed, included the direct solution method, the increment method and the Newton-Raphson method. The convergence criterions of nonline equation were also introduced.(4) The standards of the reasonable completed bridge stage of self-anchored suspension bridge and the solution methods of cable force were introduced. Based on Nanjing self-anchored suspension bridge project, stiffness support continuous beam method was applied for calculation of the cable force.(5) The specific construction procedures and the analysis methods of the bridge were introduced, included the forward analysis method, the backward analysis method and the stress-less state analysis method. The nonlinear forward analysis method was used for calculation of each construction stage, the cable forces, the internal forces and the line shapes of main beam of each construction stage were determined. The construction process can be comprehended and controlled in detail through the time travel curve of the construction stages. Finally the research work in the dissertation was concluded. 68 frame charts, 13 tables, 37 references.