Following the 1995 eathquake in Kobe district, survey was conducted on the tilt of oil storage tanks in the severely shaken area. The survey consisted in measuring elevatiosn of several points along the periphery of each tank. Some parameters indicative of levels of soundness or risk for continued operation were defined to properly analyze the vast amount of available data. Thus, the parameter "overall tilt" and "local tilt" were considered most appropriate to reflect the level of damage due to liquefaction of the ground. Features of the tanks in each farm regarding the size, scale and amount of oil contained at the time of the earthquake were introduced and summary of the damage to the tanks is presented in term of the above parameters for each group of tanks classified accordign to the scale and the kind of seismic regulation used in the design. Brief description is given concerning the soil conditions in the severely shaken areas and rough correlations are introduced between the extent of damage and the thickness of at-depth soil deposits likely to have developed liquefaction at the time of the earthquake.
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