Initial Cost And Seismic Vulnerability FunctionsFor Buildings With Energy-dissipating Devices

The current organization process stated within the framework of decision theory computes design values by minimizing the total cost of a structure, including the initial cost as well as the costs because of earthquakes. Initial cost functions are described in terms of design parameters, usually the seismic design coefficient. These functions are obtained in this paper by analyzing four different types of structures. Each structure is represented by a reinforced concrete frame comprised of beams and columns, with hysteric energy-dissipating devices installed as braces. The structures studied in this paper are hypothetical buildings built at a soft site in the Valley of Mexico with five, ten, fourteen and twenty-stories high. Cost analyses obtained for these systems are compared with those obtained for a conventional frame made up of only beams and columns. From those structures studied in this paper, vulnerability functions (drift-seismic intensity) are obtained for both systems, that is, the conventional system and the system with dissipating devices. These vulnerability functions together with the cost analyses performed are used to find cost of damage-seismic intensity relationships. 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.