Bridge Analysis For Long-Span Steel Truss Cable-Stayed Bridge

Firstly, the development of the history and current status, the design theory, and the technical progress of long-span steel truss cable-stayed bridge are summarized in the thesis. Then based on a long-span steel trussed cable-stayed bridge as engineering background, according to the related design documents, the cable elements, beam elements and plate elements of the full-bridge finite element model are established by the use of finite element software MIDAS/CIVIL2006.The following three aspects of bridge are calculated and analyzed:(1) Static analysis:The stress and deformation under dead load and construction load are calculated in the construction phase. The force and deformation under dead load, live load, system temperature, local temperature, wind load and other loads are calculated in the operational phase. The bearing capacity of bridge structure is verified;(2) Dynamic analysis:The subspace iteration method is used to calculate the bridge vibration frequencies and modes of participation in mass ratio. And the response spectrum method is applied to analyze the response of bridge under earthquake. The stress status of bridge under the combinations of dead load and seismic is obtained. Similarly the seismic capacity of the bridge is verified;(3) Stability analysis:The two-cantilever stage and the very stage before mid span closure are selected from the construction phase to discuss their stability. Also the stability analysis is applied to the completed stage of bridge and operational phase under various load conditions. The conclusions show that the stability of the bridge structure can meet the requirements.Through the full-bridge analysis for long-span steel truss cable-stayed bridge, the mechanical characteristics of the bridge are summed up. Ultimately these problems needed to be lucubrated are proposed.