NUMERICAL INVESTIGATION INTO SIGNIFICANT REDUCTION IN COEFFICIENT OF RESTITUTION FOR FLUID-CONTAINER COMBINED SYSTEMS

摘要

The analysis procedure of rocking motion of unanchored flat-bottom cylindrical shell tanks should include an impact problem between the tank bottom plate and tank foundation. To evaluate the rocking motion of tanks based on a simple analytical procedure developed by a senior author, adequate estimation of a coefficient of restitution is necessary. This paper numerically examines the coefficient of restitution suitable for the fluid-container combined system used in such simple analysis procedure. Employing free rocking motion, an empty container and fluid-container combined system are computed. The velocity vectors of the empty container turn their direction simultaneously just after the uplifted edge hits the ground, while those of the fluid-container combined system need a time to turn their direction. This implies that die coefficient of restitution should be evaluated with effects of fluid stored inrnthe tank