Fluid-structure-soil interaction effect on dynamic behaviour of circular water tanks

To investigate the seismic behaviour of concrete tanks on different soil conditions, fluid-structure-soil interaction system is simulated using finite element analysis software ANSYS. The influence of soil properties on tank's dynamic behaviour is studied by performing modal and transient analyses of cylindrical tanks resting on different soil conditions. Considering four different soil properties, comparisons are made on response parameters such as displacement in radial direction at top of tank wall, maximum hoop force, bending moment and base shear. The effect of frequency content of earthquake on seismic behaviour circular concrete tank is investigated by conducting time history analyses of the tanks under three different earthquakes. All the analyses were performed for half fill and full fill condition. Transient analyses show that the soil property, frequency content of earthquake and water fill condition have significant effect on seismic response of the water tanks.