Performance of Roofs and Floor Slabs During Bam, Earthquake of ۲۶ December ۲۰۰۳

Collapse of non-engineered roofs and floor slabs during the Bam earthquake of December ۲۰۰۳ was the single major contributor to the large fatalities during that earthquake. Different floor systems of buildings in the city of Bam can be categorised into three types namely; the traditional masonry dome or vault, the steel I-beam jack arch system and the concrete beam-hollow block system. In this paper the seismic performance of each type of flooring as observed after the Bam earthquake is discussed and their points of weakness and strength are highlighted. Also the poor seismic performance of the traditional dome and vault roofs and the unanchored jack arch slabs are noted and the seismic merits of the anchored jack arch slabs and concrete beam-hollow block slabs are discussed.