Application of an optimum design method to practical building frames with viscous dampers and hysteretic dampers

An innovative optimum design system for structures with passive-type dampers is proposed. The design system depends on the type of dampers. A realistic application example is presented first of the optimum structural design method to practical building frames with hysteretic dampers. A computer program based on the gradient projection algorithm is used for initial design of a 100 m-high building frame located at Osaka, Japan. The effect of hysteretic dampers is incorporated in the calculation of design horizontal loads. The present method has the flexibility that manual modification by structural designers can be added to the initial design in order to satisfy multiple design conditions specified in the Japanese building structural design codes. Subsequently another practical method is presented for optimum structural design of building frames with viscous dampers. This method is a two-step design procedure. The first step consists of the stiffness design of a reduced shear-building model with viscous dampers. The second step is the optimum design for building frames subjected to static design loads. The design horizontal static loads are determined in the first step. Several design examples are presented to demonstrate the usefulness of the proposed design method.