Socioeconomic Implications of Life Quality Index in Design of Optimum Structures to Withstand Earthquakes

Structures should be optimal with respect to economic investment, benefits derived from their existence, expected consequences in case of failure, and the degree of protection to human life and limb. This paper presents the implications of a new optimization strategy for the seismic design of structures. A renewal model for the sequence of structural failures is used to define the objective function of optimizing the design of structures in seismic regions. The life quality index, which is a compound social indicator, is included in the optimization for efficiency of the measures to save human lives. This criterion balances quality-adjusted life years saved against the associated cost to society. The results show that safety standards used in current practice in earthquake engineering should be reviewed in light of optimization of resources and saving human lives. They also show the importance of different socioeconomic characteristics in the definition of risk acceptability.