Collapse of non-engineered masonry jack arch roofs and floor slabs during the Bam earthquake was a major contributor to the large fatalities during that earthquake. In this paper the seismic performance of different types of jack arch roofs as observed after the bam earthquake is discussed and their weaknesses and strengths are pointed out. Also the poor seismic performance of the unanchored jack arch slabs is highlighted and the seismic merits of the anchored jack arch slabs are discussed.

كلمات كليدي:

Bam earthquake , Seismic performance , Jack arch slabs , Masonry roofs