Seismic Response of Elevated Liquid Storage Tanks Using Double Concave Friction Pendulum Bearings with Tri-Linear Behavior

Abstract

In the current paper, the seismic response of elevated liquid storage tanks using double concave friction pendulum bearings (DCFP) considering bi-linear and tri-linear behaviors have been investigated. After deriving the coupled differential equations of motion, the MATLAB programming language is employed to solve the differential equations in each time step in order to obtain the time history response of isolated tank under near fault ground motions. The advantages and disadvantages of tri-linear behavior over bi-linear one on the response of isolated tanks is scrutinized by studying the effects of main parameters such as isolation period, tank period with fixed base, tank aspect ratio and base mass ratio on the tank response. It is demonstrated that change in bearing behavior form bi-linear to tri-linear dramatically affects the bearing maximum displacement while the peak value of other parameters such as sloshing displacement or tower shear force may experience less variations.