A study on the dynamic response of upright circular cylindrical liquid
-storage tanks containing two different liquids under a horizontal bas
e motion with an arbitrary temporal variation is presented. Only rigid
tanks were studied. The response functions examined include the base
shear, base moments, and hydrodynamic pressure on the tank wall and ba
se. Unlike the cases of tanks containing one liquid, in which the resp
onse is controlled by one parameter, height-to-radius ratio, the respo
nses of tanks that contain two different liquids are controlled by thr
ee parameters: height-to-radius ratio, mass density ratio, and height
ratio of the two liquids. The response functions are evaluated for a w
ide range of values for each parameter; the results are presented in g
raphic forms. The study shows that the dynamic response of a tank fill
ed with two liquids is quite different from that of an identical tank
filled with only one liquid; the maximum sloshing wave height may incr
ease significantly, and the fundamental period of the sloshing motion
is longer in a tank containing two liquids.