Variable curvature pendulum isolator system for seismic isolation of liquid storage tanks

Variable curvature pendulum isolator (VCPI) system to isolate the liquid storage tank subjected to earthquake ground motion is proposed in this study. The effectiveness of the proposed system to isolate the tank is studied using a numerical method. Both the tank wall and fluid are modeled using finite element method considering the fluid and wall interaction at the common boundaries. The effectiveness of the proposed system to isolate the tank is studied by comparing the seismic responses of the tank isolated with VCPI system and isolated with FPS isolator. One far-field and three near-fault earthquake ground motions are considered for the study in order to investigate the effectiveness of the proposed system for varied type of earthquake ground motions. From the study, it is concluded that compared to FPS isolator, VCPI system is more effective to reduce the base shear, dynamic pressure and sloshing displacement. The sliding displacement and residual displacement of the tank isolated using VCPI system are more or less similar to that of the tank isolated using FPS isolator.