Seismic fragility assessment of low-rise unreinforced masonry buildings in the Kurdistan region of Iraq

The collapse of building structures during recent earthquakes, particularly in the countries around the Kurdistan region (KR), such as Turkey (2011 Van earthquake) and Iran (2003 Bam earthquake), has raised many questions about the safety of existing buildings in the region and those structures that are going to be constructed in the future. The KR, which is located in the north and northeastern parts of Iraq, is also considered to be the most hazardous part of Iraq. However, many buildings in the region, especially the unreinforced masonry buildings, were not engineered to withstand seismic loads. This paper investigates the seismic fragility of existing unreinforced masonry buildings in KR in terms of their fragility curve and surface using an analytical approach. This study considers many factors, including the variability of the mechanical properties of materials, ground motion intensity measures (IMs), a number of ground motion records and their effect on the selection of IMs and thus the derivation of the fragility curves. The results demonstrate that unreinforced masonry low-rise buildings in the KR are highly vulnerable to seismic loads and that such structures must be strengthened to prevent failure.