Seismic Response of Liquid Storage Tank Isolated with Double Sliding Isolator with Variable Curvature (DSIVC)

Abstract

The paper describes the earthquake response of liquid storage tank that has been isolated with double sliding isolator with variable curvature (DSIVC). Under six near-fault bilateral earthquake ground excitations, a DSIVC isolated liquid storage tank is studied. A DSIVC isolator is made up of two sliding surfaces variable in curvature and slider positioned between the two sliding plates. A double sliding isolator has double isolator displacement capacity compared to single sliding isolator with same size therefore flexibility in designing. A geometric function formula is used to calculate the response quantities from a liquid storage tank that has been isolated with DSIVC. Newmark's step-by-step approach is used to solve a governing equation of motion. Convective, impulsive, and rigid masses are linked to a liquid storage tank detached using DSIVC. A DSIVC-isolated liquid storage tank has four response quantities: Convective, impulsive and isolator displacement, and base shear. For parametric study DSIVC isolator four design cases are considered for different geometry of sliding surfaces at the top and bottom and values of response quantities obtained. A liquid storage tank isolated using DSIVC isolator is compared to the identical liquid storage tank isolated with DVCFPS for a comparative research. It was observed that isolator displacement and convective displacement reduces after installation of DSIVC and base shear and impulsive displacement increases after installation of DSIVC as compared to DVCFP isolated liquid storage tank.