The effectiveness of braces depends on brace placement and stiffness. Therefore, in meeting the design target story stiffness, both of these parameters should be optimized to achieve the highest effective brace deformation. In this paper, a method for this is proposed by presenting a relationship between brace placement, brace stiffness and effective brace deformation ratio. This relationship is derived by using an equivalent spring model that considers the effect of axial deformation of columns and seismic isolation bearings. Through several examples of mid-rise base-isolated building models, it is demonstrated that the effectiveness of various brace placements can be quantitatively evaluated.
