Vulnerability functions and the influence of seismic design parameters on initial costs for buildings provided with hysteretic energy-dissipating devices

摘要

This paper is intended to attain both the influence of seismic design parameters on initial cost and seismic vulnerability functions for reinforced concrete buildings provided with hysteretic energy-dissipating devices. In order to obtain this, an established methodology for earthquake resistant design is applied to different types of buildings. In the optimization process, in order to attain optimum design values, it is necessary to have both initial cost functions, as well as costs due to earthquakes. Initial cost functions are described in terms of design parameters, usually the seismic design coefficient or the vibration period. The influence of seismic design parameters on the initial cost is first studied, and then functions relating costs of the structures to the design parameters are obtained. In order to do this, we analyze different types of reinforced concrete buildings where each one is represented by a reinforced concrete frame composed of beams and columns, with hysteretic energy-dissipating devices installed as braces. The structures studied are hypothetical buildings built at a soft site in the Valley of Mexico with a different number of stories. Cost analyses obtained for these systems are compared with those attained for a conventional frame just composed of beams and columns. Vulnerability functions (drift-seismic intensity) are obtained from those structures studied here. These vulnerability functions together with the cost analyses performed are used to find the cost of damage-seismic intensity relations. The results show that the use of systems with energy-dissipating devices gives a better cost-benefit behavior when the system is under high seismic intensities. Moreover, these results are appropriate for performing long-term cost-benefit analyses.