Members Sizing of Optimum Bracing of Fixed-base Steel Frames

To design steel structures so as to make them potent to tolerate lateral loads, lateral load resisting systems are considered which may be in the form of moment frame rigid or semi rigid connections, pre-qualified bracing systems or dual systems. The typical pre-qualified bracing systems are first prescribed based on architectural considerations etc. and then the structural design process is run to size the profiles needed to be assigned to these usually slant members. However, to minimize the material used to fortify the structure against lateral loads, an optimum topology may be determined through optimizing the layout of the lateral load resisting system. The design process can be then performed to determine the sizes of the profiles which are to fill in the optimal topology of the frame. The outcome of this optimal design process, namely topology optimization and corresponding sizing determination, is idealistically a scheme with minimal lateral load bearing material and proper lateral performance of the structure. In this research such a sizing scheme is taken to offer eventual designs of steel frames. The material used to brace frames with constant beams and columns is observed to be considerably less than that used in typical design procedures while the performance of the frames remain logically suitable.

Keywords:

topology optimization , braced steel frame , member sizing , lateral load , required material