Study On Optimization Design Of Concrete-filled Steel Tubular Structure

Concrete-filled steel tubular structure is of many advantages, such as, good ductility, high bearing capacity, short construction time and economic benefits. Concrete-filled steel tubular frame structure system has become one of the important form of construction in high-rise and large-span buildings in recent years. However, the studies on the concrete-filled steel tubular frame structure mainly concentrate on the computing theory and basic behavior, roughly on the optimal design of structure, which render the non-necessary material waste and restrict the application of concrete-filled steel tubular structure. Therefore, searching for reasonable optimization design methods in order to enhance the economic benefits of this construction structure has become a hot topic in engineering both at home and abroad.This paper utilizes the three-dimension solid element(Beam188) of finite-element analysis software to establish the finite-element analysis model and use the elastic-plastic theory of solid mechanics to calculate and analyze concrete-filled steel tubular frame structure, which elects shear modulus and combination of bending modulus as the cross-section modulus of concrete-filled steel tube, obtaining accurate internal forces of structure under the compression. Then, to avoid the defect of slow convergence rate and trapping in local optimum of Ant Colony Algorithm (ACA), the strategy for refreshment of pheromone in ACA was improved and the improved ACA was used for the optimization design of concrete-filled steel tubular structure. The optimal model of concrete-filled steel tubular frame structure was established, in which, the aiming function is the minimal cost. On the basis, utilizing MATLAB to compiling optimization program for the steel beams and framework of the concrete-filled steel tube columns, obtaining the optimization-results of members and framework structure of concrete-filled steel tube with ACA and comparing the results with the statistics obtained in ANSYS on the internal forces and economy. Results shows that the improved ACA is fit for the optimization of concrete-filled steel tubular frame structure on the premise that the bearing capacity is more or less the same and satisfy the designing requests, the statistics is reliable and efficient.This paper applies intelligent algorithm to the optimization of concrete-filled steel tubular frame structure, which has a certain realistic significance for the improvement of this kind of structure’s designing-theory and provides a certain reference for the scientific optimization of construction structure.