Seismic Risk Assessment of Nonengineered Residential Buildings: State of the Practice

The poor socioeconomic conditions in developing countries often lead to poorly constructed residential buildings that are particularly vulnerable to damage during an earthquake. A review of available literature carried out as part of a larger research program highlights the scarcity of existing fragility curves for the wide typology of nonengineered residential buildings around the world. Furthermore, fragility curves derived using empirical data are almost nonexistent due to the lack of postearthquake damage data and insufficient ground motion recordings in developing countries. The diversity in construction techniques and material quality in developing countries, particularly for nonengineered residential buildings, cannot be sufficiently represented through simplified or idealized analytical models. Therefore, the use of empirical based fragility curves is considered to be a well-suited approach for assessing the seismic risk levels for nonengineered residential buildings in developing countries. This paper presents a review and evaluation of existing seismic risk assessment studies and state-of-the-practice as it pertains to nonengineered buildings, and subsequently proposes the use of attenuation-based USGS ground motion and shaking intensity maps and geographic information system damage information to derive relevant fragility curves. The USGS ground motion and shaking intensity maps are proposed as they are developed using a consistent robust methodology.