| Bimetal full containment LNG storage tank has been widely used in urban LNG storage and distribution stations and peaking-shaving stations due to its advantages of small investment and short construction period.LNG storage tank has a large containment.If the tank structure is damaged in an earthquake,accidents such as leakage will occur.This paper analyzes the seismic response of 10000m~3bimetal full containment LNG storage tank,which provides a reference for the structural design of storage tank.Based on the fluid-structure coupling theory,a structural model of LNG storage tank was established,and the deformation,stress and stability of the inner tank were calculated and analyzed under the conditions of the highest liquid level and hydraulic pressure test.Based on the modal calculation of the tank under three conditions:empty,full hydrostatic load and fluid-structure coupling,the basic period of liquid sloshing is obtained,the influence of liquid on the modal of the tank is analyzed.The calculation results of the first 1000 modes of the tank show that the main modes are local liquid level fluctuation and liquid storage sloshing when the frequency is low.When the frequency gradually increases,it reflects many vibration modes such as annular multi-wave,and the fluid-structure coupling vibration is mainly beam-type vibration.The frequencies of the first four orders of beam-type vibration are 3.60,5.13,9.85 and13.62Hz.By analyzing the dynamic response of the storage tank under the action of unidirectional and bidirectional seismic waves,it can be seen that the vertical seismic wave has influence on the deformation and stress of the storage tank,but the vertical seismic wave has little influence on the height of the reservoir wave.Through the analysis of the bottom wall of the storage tank,it is found that although the axial stress exceeds the standard,but the hoop stress does not exceed the standard,and the storage tank does not appear"elephant foot"buckling. |
PDF Full Text Request