Published online by Cambridge University Press: 15 September 2010
The long-period components in earthquake ground motions, which attenuate gradually withdistance, can induce sloshing waves in the liquid containment tanks although they arelocated far away from the seismic source. The resulting sloshing waves generate additionalforces impacting the wall and roof of the tanks and may cause extensive damage on the tankstructure. Numerous examples of tank damages due to sloshing of fluid have been observedduring many earthquakes. Nevertheless, the effect of sloshing is usually primitivelyconsidered in most of the seismic design codes of tanks. On the other hand, the derivationof an analytical solution for the sloshing response of a liquid storage tank subjected toharmonic excitation includes many assumptions and simplifications. Most of the analyticalsolutions in the recent literature assumed the containing liquid to be invicid,incompressible and irrotational, and the tank structure to be an isotropic elastic platewith uniform stiffness, mass and thickness. Even though, experimental works are necessaryto study the actual behavior of the system, they are time consuming, very costly andperformed only for specific boundary and excitation conditions. However, appropriatenumerical simulation using fluid structure interaction techniques can be used to predictthe hydrodynamic forces due to the high-speed impacts of sloshing liquid on a tank walland roof. These simulations can reduce the number of experimental tests. The nonlinearfinite element techniques with either Lagrangian and/or Eulerian formulations may beemployed as a numerical method to model sloshing problems. But, most of the Lagrangianformulations used to solve such problems have failed due to high mesh distortion of thefluid. The arbitrary Lagrangian Eulerian techniques are capable of keeping mesh integrityduring the motion of the tank. In this study, an explicit nonlinear finite elementanalysis method with ALE algorithm is developed and sloshing phenomenon is analyzed. Theanalysis capabilities of the method are explained on a technical level. Although, thedeveloped numerical procedure is applicable to deformable structures, the accuracy of themethod is validated with the existing analytical formulation derived from potential flowtheory as well as the experimental data carried out on rigid tanks when subjected toharmonic and earthquake ground motions. High consistency between numerical andexperimental results in terms of peak level timing, shape and amplitude of sloshing wavesis obtained not only for non-resonant excitation but also for resonant frequencymotion.