Integrated optimum design of viscoelastically damped structural systems

This paper describes a new approach for an integrated optimum design of a viscoelastically damped structural system. The criterion selected for the optimization is minimization of the life-cycle cost that mainly consists of the initial construction cost and the damage cost estimated by failure probability over its entire lifetime. Considering the structure and dampers as a combined or an integrated system, the characteristics of the system and the design constraints can be accounted for from the design step. Optimization problem is also formulated by adopting structural sizing variables, locations and the amount of the viscoelastic damper as design variables. A genetic algorithm is used as a numerical searching technique in order to simultaneously find the optimum parameters of the integrated system. The proposed design method was verified with a numerical example of an eight-story building. From comparative results, it is found that the integrated design approach can improve the seismic performance of the structural system while it maintains low life-cycle cost.