EARTHQUAKE OBSERVATION AND NUMERICAL ANALYSIS OF HYDRODYNAMIC PRESSURE ON ANNULAR AND CYLINDRICAL TANK.

The earthquake observation was carried out on an actual tank, which is annular and cylindrical, made of a prestressed concrete and is on a pile foundation. The accelerations, hydrodynamic pressures and strains of reinforcing bars were recorded for 16 earthquakes. The observed data were processed using A-D conversion and spectrum analysis. The observed results were checked by the numerical analysis which is based on two kinds of method, one is an analytical solution by potential theory and another is a finite element method using a coupled fluid-structure model. It was concluded that the stresses of the side wall were induced mainly by the dynamic water pressure acting on the side wall and that the dynamic water pressure was magnified due to the coupled fluid-structure motion.