Optimization Design And Parameter Analysis Of Portal Frame Light Steel Structure Building

Portal frame light steel structure building is one representative of light steel structure in china, one of the most widely structure shape at present. But ,if dimension of portal frame is unreasonable, steel weight can increase. At present, design of portal frame general use trial-and-error method in china: Define the primary parameter (structure arrangement of portal frame and section types of various components); and then, choose the section size according to restriction conditions (basis for design code: strength, stiffness and stability of components); After making proper correction according to structural calculation, it may be used as the final repair scheme. We get relation between steel weight of optimized structure and the section size by sectional optimal analysis. So it is important to proposed rationalization suggestion according to the analytical results.The paper is using APDL programming for the portal frame optimization and analyze on the basis of finite element analysis with the soft ware ANSYS with the least steel weight per unit area as the objective function, with strength ,rigidity and stability of every components as state variables, with section size of every components as design variables. This method is effective by verification an example. The optimization result is reliable and reaching the optimization purpose, so this method may use in future research. This analysis parameters, such as, span, distance between columns, gradient of beams, height of columns and make some reasonable proposals on the analysis.