| Self-anchored suspension bridges are increasingly popular for no earth anchor, less influence by geological condition and aesthetic appearance. Now this type of bridge is applied to more and more medium and small-span bridges in cities, even large-span bridges over rives.According to domestic practices, the following tasks have been completed in this paper:1. The correlative information about self-anchored suspension bridges at home and abroad is collected and studied, and structure forms ,stress features and typical anchorage structures are summarized2. Non-linear factors to self-anchored suspension bridge are analyzed, and the solution method of non-linear equations is introduced. According to the assumption of cable element, not only cable equations of 2D and 3D but also spatial cable tangent stiffness matrix are deduced. Finally cable equations using in this paper are chosen on the basis of comparison.3. Based on calculation method of plane cable shape, according to 3D cable equations, spatial cable shapes at bridge-completed stage and cable-finished stage are calculated by the numerical-analytical method such as the catenaries method of gravity distributing equally along the curve. Then taking a bridge as a case, the results for two above condition are compared. It is pointed that the method considering the saddle is shown of reality agreement, high accuracy and more convenience than Finite Element Method. The method without considering the saddle is simple and fit for preliminary calculation for cable shape.4. Taking a bridge for example, the 3D finite model composed of shell element is used to analyze the stress disturbing of main loaded members of steel anchorage and to summarize the force transmission route. Changing the parameters such as thickness of end plate and force-transmit plate, thickness and height of supporting plate and stiffening plate for optimization of the structure, the effects on end plate and force-transmit plate and their functions is determined.
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