Design method for seismic centrifugal model tests on liquid-storgae tank-pile group interaction

The LNG storage tank is a significant national strategic energy reserve project, rapidly developing towards ultra-high capacity, ultra-large diameter and semi-underground, with extremely high seismic safety requirements. In this study, aiming at the size limitations of the centrifugal model test specifications, a design method for seismic centrifugal model tests on LNG storage tanks is proposed, which takes the natural vibration period, sloshing period and bending stiffness of the tanks as the main control parameters. The dynamic centrifugal model tests are carried out on a large storage tank with a prototype of 270000 m³, the rationality of the design method is verified, and the seismic response of the storage tank is analyzed. The results indicate the natural vibration period of the storage tank obtained by the tests is close to the value of the specification, differing by 5.4%, which verifies the reliability of the test design method. The sloshing frequency of the liquid storage has little relationship with the change of the load amplitude, mainly relates to the shape of the tank, liquid level height, while the liquid sloshing wave height and the load amplitude show a significant positive correlation. The pile foundation can improve the safety of the LNG storage tanks, and under the same load excitation, the sloshing wave height of the piled tanks is reduced by about 8.2% compared with that of the unpiled tanks.