Performance of RC elevated liquid storage tanks installed with semi‐active pseudo‐negative stiffness dampers

Abstract

The effect of semi-active pseudo-negative stiffness dampers (SAPNSDs) on the seismic response mitigation in the reinforced concrete (RC) elevated liquid storage tanks is investigated. The SAPNSDs are operated in two modes: Passive-ON and Passive-OFF. The effect of placement (location) of the dampers is also studied by placing the dampers in three different configurations. Two aspect ratios of the tanks, viz., 0.5 and 2.0, are considered to study the effect of the variable level of the liquid in the container. Time history analysis is carried out for total of 18 different earthquake ground motions. The differential equations of motion are solved by the state-space approach. The response quantities such as peak base shear, overturning moment, container level displacements, and bracing level displacements, along with the damper forces, are obtained. It is found that the SAPNSDs (Passive-ON) effectively control the response of the RC elevated liquid storage tanks. Further, seismic energy input to the structure without SAPNSDs and the percentage energy dissipated by SAPNSDs is obtained. The placement of the dampers plays a significant role in response reduction during ground motion with high peak ground acceleration (PGA) than that with low PGA. The SAPNSDs installed at alternate levels (Configuration II) is the most efficient configuration for response control of the RC elevated liquid storage tank installed with the SAPNSDs. The seismic input energy reduces considerably by the installation of the semi-active pseudo-negative stiffness dampers (SAPNSDs).