influence of nonlinear fluid viscous dampers on seismic response of rc elevated storage tanks

influence of nonlinear fluid viscous dampers on seismic response of rc elevated storage tanks

the numerical investigation on the seismic response of rc elevated liquid storage tanks installed with viscous dampers is presented. a discrete two-mass model for the liquid and multi-degree of freedom system for staging, installed with the dampers are developed for reinforced concrete (rc) elevated liquid storage tanks. the elevated tank is assessed for seismic response reduction when provided with linear viscous damper (lvd) and nonlinear viscous damper (nlvd), installed in the staging.

the rc elevated liquid storage tanks are analyzed for two levels of liquid containment in the tank, 100% and 25% of the tank capacity. three configurations of placements of dampers viz. dampers at alternate levels (configuration i and configuration ii) and dampers at all the panels of the staging of the tank (configuration iii) are considered. to study the effect of peak ground acceleration, eight real earthquake time histories with accelerations varying from 0.1 g to 0.93 g are considered.

the nonlinearity in the viscous damper is modified by taking force proportional to various velocity exponents. it is found that the nonlinear viscous dampers with lower damping constant result in a comparable reduction in the response of rc elevated liquid storage tank, to that of linear viscous dampers with higher damping constant. a lower damping constant signifies compact the size of the damper.