Probabilistic Benefit-Cost Analysis for Earthquake Damage Mitigation: Evaluating Measures for Apartment Houses in Turkey

Abstract

In the wake of the 1999 earthquake destruction in Turkey, the urgent need has arisen to evaluate the benefits of loss mitigation measures that could be undertaken to strengthen the existing housing stock. In this study, a benefit-cost analysis methodology is introduced for the comparative evaluation of several seismic retrofitting measures applied to a representative apartment building located in Istanbul. The analysis is performed probabilistically through the development of fragility curves of the structure in its different retrofitted configurations. By incorporating the probabilistic seismic hazard for the region, expected direct losses can be estimated for arbitrary time horizons. By establishing realistic cost estimates of the retrofitting schemes and costs of direct losses, one can then estimate the net present value of the various retrofitting measures. The analysis in this work implies that, even when considering only direct losses, all of the retrofitting measures considered are desirable for all but the very shortest time horizons. This conclusion is valid for a wide range of estimates regarding costs of mitigation, discount rates, number of fatalities, and cost of human life. The general methodology developed here for a single building can be extended to an entire region by incorporating additional structural types, soil types, retrofitting measures, more precise space- and time-dependent seismic hazard estimates, etc. It is hoped that this work can serve as a benchmark for more realistic and systematic benefit-cost analyses for earthquake damage mitigation.

Review of retrofit strategies decision system in historic perspective

“…5). When evaluating the efficiency, the decision problem becomes a single criterion one (like in the method described in Smyth et al, 2004), while if the chosen solution is not efficient the decision process is set back to the first stage, a multi-criteria one, where constraints have not been yet converted to the same unit of measure.…”

Vulnerability assessment and feasibility analysis of seismic strengthening of school buildings

“…Section 2 provides fragility curves for each building type under consideration, prior to, and after, the considered strengthening schemes, similarly to Smyth et al (2004). Thus, the vulnerability of the strengthened building is expressed through corresponding fragility curves, and the efficiency of the strengthening (R) is estimated from the decrease of the pertinent damage probabilities (e.g.…”

Proceedings of the Measurement Science for Sustainable Construction and Manufacturing Workshop Volume I. Position Papers and Findings

“…(Erdik et al 2005) and (Korkmaz 2009) provided losses assessment models for long-term disaster management considering probabilistic seismic hazards. Also, different methodologies and frameworks for seismic loss estimation have been developed and used to conduct a benefit-cost analysis for different seismic retrofit alternatives (Smyth et al 2004), (Kappos and Dimitrakopoulos 2008) and (Valcárcel et al 2013). Correspondingly, a number of standardized software packages have been developed with friendly user-interface and open-source database.…”