چكيده لاتين :
On-grade cylindrical tanks are important components ofmany industrial
complexes such as oil refineries. The seismic behavior of un-anchored cylindrical
liquid storage tanks is highly dependent on height to diamet er ratio (HID) and
volume ofcontained liquid. Hence, in this study based on the differences in seismic
performance of tanks of various aspect ratios. a certain aspect ratio is selected as a
margin ofbroad and tall tanks. Furthermore, the contribution ofvolume ofcontained
liquid in seismic performance of the tanks was investigated. Results of this study
revealed that the aspect ratio ofHID=0.6 can be considered as a marginal value of
aspect ratios of broad and tall tanks. In other words. a tank can be considered as a
broad tank if the aspect ratio is great er than 0.6; otherwise it should be considered
as a tall tank. The freeboard level of the contained liquid. plays a major role in the
seismic performan ce of liquid storage tanks. The significance of such effects is
dependent to the HID ratio of the tank. Although in broad tanks the shell stresses
decrease gradually by decr easing the volume of the liquid. but tall tanks behave in
various manners by changing the volume ofthe fluid.
