Seismic Performance of Anchorage in Liquid Storage Steel Tanks by Added-Mass Method

The sophisticated deformed configurations of liquid storage tanks and theinteraction between fluid and structure give rise to a wide variety of possiblefailure mechanisms during strong ground motions. Base-anchorage failure,foundation differential settlements, shell buckling as elephant’s foot and diamondshapebuckling, large deformation of shell at roof elevation due to sloshing effectsare common recorded failure modes of storage steel tanks in the earthquakes.Among the failure modes, base-anchorage performance using force-controlmethod is what this paper has focused on. In that regard, a cylindrical steel tank isselected in order to investigate various aspects of dynamic loadings on the tankseismic responses. In this study, the added-mass method is used in the finiteelement modeling of the steel tank and fluid, and the numerical analyses areperformed. Few previous studies have shown that the added-mass method mightprovide more accurate results in the study of dynamic interaction betweenstructures and reservoir systems, particularly, if the local effects were deemed.The added-mass method results are compared to the conventional methodoutcomes using two or more lumped-mass and equivalent springs for tank-liquidsimulation (Housner method). It is found that the added-mass method results ingreater forces on the anchors in comparison to the lumped-mass method.

کلیدواژه ها:

Steel Tank ، Added-Mass ، Anchor ، Lumped-Mass ، Dynamic