Document Type : Structural Earthquake Engineering
Sloshing Wave Impact Force (SWIF) caused by liquid motion during seismic excitations is investigated in this paper. When the freeboard is insufficient, the liquid waves collide to the tank roof on which uplift forces are produced. Due to the complication of sloshing impaction, there is no comprehensive investigation that can clarify the various aspect of this phenomenon. Therefore, most of standards don’t recommend any method to evaluate SWIF. Alternatively, the main approach of related codes and standards is to suggest a required freeboard in order to prevent collision of sloshing wave to the tank roof instead of evaluating the SWIF. However, suggested freeboard is too high to meet economic considerations in some cases. Therefore, the impact forces should be reasonably evaluated based on the experimental measurements and analytical solutions. An experimental investigation has been implemented to clarify the influence of various geometrical parameters on the impact roof pressure and force values of a rectangular tank. A series of shaking table tests are conducted for a partially filled rectangular tank under harmonic and different earthquake excitations. The experimental measurements for SWIF are compared with those recommended by code provisions and the effects of various parameters on SWIF are discussed.