| Abstract:Concrete-filled steel tubulur arch bridge has been widely used in bridge construction in our country, but its theory research is far behind the practical application. During the design of a concrete-filled steel tubulur arch bridge, due to the large number of design parameters and mutual coupling between parameters, scheme adjustment is complicated, it’s difficult to get reasonable and economic target with meeting the requirement of the whole bridge static and dynamic performance, so it’s necessary to use the modern optimization theory to carry on the design process of the automatic optimization.On the basis of summarizing the research results of predecessors, this article put forward a corresponding optimization model, with a through concrete-filled steel tubulur arch bridge under construction as example, compiled the optimization program with ANSYS Parameter Design Language, strived for researching the optimization method of dynamic and static performance of the concrete-filled steel tube arch bridge. Main works of this article are as follows:1) Analyzed the ranges of arch axis and cross-section values of concrete-filled steel tubulur arch bridge.2) Proposed to use arch axis and cross-section parameters as design variables, use arch steel and concrete stress, pier concrete stress, web member steel stress, deflection with live load affection and stability coefficient as constraints, use structural frequency as objective function, establish the optimization mathematical model.3) Based on ANSYS Parameter Design Language, built ANSYS space finite elements model and simulated the construction process accurately, compiled the live load loading program and the concrete creep analysis program.4) Selected the optimization algorithm, compiled optimization program, optimized arch axis and cross-section, compared the design variables, constraints, and objective before and after optimization.5) Analyzed earthquake response spectrum of the models before and after optimization and then compared seismic forces of the twice conditions, for verifying the effectiveness and feasibility of the optimization method in this article.The result shows that:with the optimization model has been established in this article, after optimization, the dynamic performance is improved substantially, the internal forces under seismic load is decreased obviously, and the total cost is reduced greatly, the effectiveness and feasibility of the optimization method get verified. |
