Rolling isolation test on vertical cylindrical tank

In order to analyze the damping effects of rolling isolation devices on vertical cylindrical tanks, the model test was conducted on the vertical cylindrical tank using the shaking table of earthquake simulation. The model of vertical cylindrical tank was designed according to the similarity ratio of 1:4, and the measuring points of the acceleration sensors were arranged in the circumferential direction at different heights of the tank wall. Then, three kinds of earthquake waves (El-Centro wave, Pasadena wave and Kinmen earthquake wave) were input. Finally, acceleration and lifting displacement of the tank were measured and compared with those of the vertical cylindrical tank with the traditional earthquake-resistance structure system which has no rolling isolation device. It is shown that the acceleration response at the bottom of the tank is reduced by 49.49%-62.47% when the isolation control system is adopted, and the earthquake resistance design can be conducted on the basis of the decreased intensity. Furthermore, by virtue of rolling isolation, the lifting height of vertical cylindrical tank is decreased significantly, and the damping efficiency of the lifting is 28.5% under the action of Kinmen earthquake wave and 76.6% or more under El-Centro wave and Pasadena wave. As a result, elephant-foot buckling or cracking damage of big fillet weld can be effectively prevented.