PERFORMANCE-BASED DESIGN OPTIMIZATION OF STRUCTURES UNDER SEISMIC DEMANDS, INCORPORATING PASSIVE CONTROL DEVICES

Performance-based design in earthquake engineering is a structural optimization problem that has, as the objective, the determination of design parameters for the minimization of total costs, while at the same time satisfying minimum reliability levels for the specified performance criteria. Total costs include those for construction and structural damage repairs, those associated with non-structural components and the social costs of economic losses, injuries and fatalities. This paper studies the influence, on the optimization results, of incorporating energy dissipation devices based on steel yielding. We use a general framework to approach this problem, using a numerical optimization strategy and incorporating the use of neural networks for the evaluation of dynamic responses and the reliability levels achieved for a given set of design parameters. The strategy is applied to an example of a four-story office building, with energy dissipation devices located at each floor level. Optimum results show that a minimum control force and stiffness is necessary to reduce the replacement of control devices after the occurrence of earthquakes, which increases the total life cycle cost (LCC).