The Research On Structural System And Static-Dynamic Mechanics Performance Of Long-span Self-anchored Suspension Bridges

In recent years, many long-span self-anchored suspension bridges have been constructed because this type of structure has lots of merits such as graceful appearance, new type of structure and convenience in choosing bridge location. To ensure self-anchored suspension bridges'safety during construction and service, and to make its design more economical and reasonable, the research on structural system and static-dynamic mechanics performance of the long-span self-anchored suspension bridges is developed in this paper based on Pingsheng Self-anchored Suspension Bridge in Foshan city, Guangdong province. The main contents and achievements are as following:1. Based on the virtual work increment equation of updated Lagrangian formulation, tangent stiffness matrix of spatial beam/truss element is obtained. According to base assumptions and catenary equation of cable, the iterative formulations of tangent stiffness matrix and nodal force of the spatial two-node catenary cable element are put forward. Therefore the entire geometrical non-linear finite element theory for the analysis of suspension bridges is established.2. Based on the basic design data and requirements, the designs on the new type of structural system of Pingsheng Bridge are proposed. A lot of creationary achievements will be acquired on Pingsheng Bridge, called the single tower self-anchored suspension bridge.3. Based on the geometrical non-linear finite element theory, a fine iterative method of simulating all construction stages of self-anchored suspension bridge is proposed and used to Pingsheng Bridge. The construction plans of suspension rod and second dead load are discussed in details. The model test of Pingsheng Bridge is completed. The research results indicate that it is the best plan for suspension rod to be constructed from main tower to side pier and for second dead load to be loaded before the bridge has been completed. Analysis results are very close to test results, which show the proposed iterative method has the high precise. In addition, the analysis and test for the entire stability and limited carrying capacity are completed and results show that Pingsheng Bridge is also safe enough.4. The influence on the static performance for Pingsheng Bridge of structural parameters, such as rise-span ratio of main cable, stiffened girder rigidity, main tower rigidity and main cable rigidity, is studied. Dynamic performance of Pingsheng Bridge and the ground-anchored suspension bridge model, which has the same structural parameters as Pingsheng Bridge, is calculated. Furthermore, the influence on dynamic performance for Pingsheng Bridge of structural parameters, such as rise-span ratio of main cable, dead load...