Experimental investigation on the seismic isolation for a legged wine storage tank

Abstract

Because of the booming of the winery industry in some seismic countries such as, the U.S, Italy, Chile and Argentina,the seismic protection of wine storage tanks may be of a practical importance. Previous numerical and theoreticalinvestigations have shown that seismic isolation can reduce the seismic demand on liquid storage tankscompared to the fixed base case. However, there are not experimentalworks about the seismic performance andprotection of leggedwine storage tanks, nor practical applications, reported in the technical literature. Therefore,in this paper, the effectiveness of a novel seismic isolation system has been investigated by shaking table tests ona full-scale legged tank, typically used in the wine industry. A comparison of the seismic behaviour of fixed baseand isolated base configurations is presented. Two alternative base isolation systems have been studied: flat slidingbearings with a central leg acting as restoring element, and flat sliding bearings without any restoring element.The restoring force of the central leg was performed by means of five compression springs. Theexperiments were carried out using 3 natural and 3 artificial records. Measurements were made of the shearand axial forces in one leg of the tank, and the horizontal displacement of the tank. The experiments showedthe beneficial effects of using the proposed isolation system in legged wine storage tanks, reducing the shearand axial forces in comparison with the fixed base configuration and reducing the horizontal displacement comparedto the flat sliding bearing configuration without any restoring element.