# Seismic Response of a Large LNG Storage Tank Based on a Shaking Table Test
## 1 Introduction  
With the continuous development of the social economy, the demand for energy is increasing all over the world. Under the background of vigorous energy demand, the total consumption of liquefied natural gas (LNG) in the world continues to increase, reaching 487.9 billion cubic meters in 2020. As countries around the world attach importance to environmental protection, the use of clean energy in various countries will continue to increase. This means that in the future, countries around the world will continue to expand the import of natural gas and the construction of LNG storage tanks will usher in a new historical opportunity. LNG storage tank is a device for storing and transferring liquefied natural gas, making it an important lifeline project, and its safety performance is equivalent to that of nuclear power facilities. The LNG storage tank is mainly composed of a concrete outer tank, steel inner tank and thermal insulation material, and LNG is stored in the steel inner tank. In order to ensure the safe operation of the storage tank and prevent the leakage of liquefied natural gas during the service period, the storage tank needs to have a high seismic capacity. In order to improve the safety performance of storage tanks under the action of earthquakes, it is of great academic and engineering value to conduct seismic isolation experiments and theoretical research on storage tanks. In previous seismic research of storage tanks, many scholars have carried out work based on simplified models or numerical simulations of storage tanks. [PERSON] [1] proposed a rigid wall model for the simplified calculation of storage tanks, which divides the liquid into a rigid part and a convection part. Subsequently, [PERSON] and [PERSON] [2] and [PERSON] et al. [3,4] also proposed a more reasonable simplified model of storage tank, respectively. [PERSON] [5] et al. proposed a simplified seismic design method for cylindrical anchored storage tanks, which considers the effects of liquid pulsation and convection on the tank wall, and the model proposed by the latter was adopted by Eurocode 8 [5]. With the increase in storage tank volume, the safety performance requirements of the storage tank are also increasing. The previously developed seismic theory of storage tanks is difficult to meet the design requirements, so the research on seismic isolation theory of storage tanks is put on the agenda. [PERSON] and [PERSON] [6,7] studied the dynamic response of the storage tank isolated by the sliding system under the action of ground motion and analyzed the parameters affecting the isolation of the storage tank. [PERSON] et al. [8] studied the seismic isolation effect of multi-friction pendulum bearings on LNG storage tanks based on the Malhotra model [5]. The results show that the multi-friction pendulum bearings have excellent seismic isolation effects at different liquid levels. [PERSON] et al. [9, 10, 11] and others studied the random response of two typical inert isolation system storage tanks using an analytical method and proposed an optimal design method based on the performance requirements of the liquid storage tank. [PERSON] et al. [12] proposed an optimization design method based on a closed analytical solution for inert isolation storage tanks. [PERSON] [13] established a five-particle model considering the influence of higher-order sloshing modes on LNG storage tanks. In order to verify the effect of the isolation device in the LNG storage tank, many scholars have carried out research on it using finite element software. [PERSON] et al. [14] analyzed the seismic responses of the isolated and non-isolated storage tanks and found that the lead-core rubber bearing has a good seismic isolation effect. [PERSON] et al. [15] used the acoustic-structural coupling method to numerically simulate a cylindrical liquid storage tank with base isolation, and found that the impulse pressure on the tank wall was reduced after the introduction of the isolation device.