Economic Feasibility Analysis of Pre-earthquake Strengthening of Buildings in a Moderate Seismicity / High Vulnerability Area

Abstract

While regions with high seismicity have been widely investigated, areas with moderate seismic hazard has not been fully adequately studied as being exposed to high risk due to their vulnerable built environment. A standardized and straightforward risk assessment methodology is needed for public authorities in moderate seismic / high vulnerability areas to assess the potential seismic risks and to make corresponding structural strengthening plans for protecting properties and people's lives. Adopting the standardized seismic loss assessment tool HAZUS, this study aims to present the methodology for investigating the economic feasibility of the pre-earthquake structural strengthening of buildings by means of benefit-cost analysis. Therefore, the specific objectives of this study are to: (1) to assess the seismic risks with building and demography parameters which can fully represent the characteristic of local built environment, (2) to conduct benefit-cost analysis of the seismic mitigation activities, and (3) to verify the applicability of the present methodology by a case study. To assess risk from earthquake hazards, both deterministic and probabilistic earthquake scenarios were simulated, combined with micro-zoning studies, geological characteristics, building inventories, population distribution, and adaptation of the building fragility curves and casualty matrix to the local conditions. This study intends to provide public decision makers a standardized methodology for justifying the economic feasibility of seismic risk mitigation alternatives so that a cost-efficient public earthquake mitigation strategy can be achieved.