Earthquake-resistance Analysis Of Large Unanchored Vertical Cylindrical OiL Storage Tank

The lifeline system consists of four systems:energy,water,communication,and trans-portation.Oil storage tanks are the main storage equipment for non-renewable energy such as petroleum.Since the seismic dynamic response of oil storage tanks is very complex,the analysis of seismic performance is very valuable for research.In this paper,analyzes the earthquake resistance of a large unanchored vertical cylindrical oil storage tank with a vo-lume of 15×10~4m~3.The three-dimensional finite element model of the storage tank was es-tablished in the ABAQUS software,and the contact between the storage tank and the ground was simulated.Firstly,according to the modal analysis and static analysis of the storage tank,study the characteristics and static effects of the storage tank itself.Secondly,Considering the solid-liquid coupling effect,study the dynamic time-history response of oil storage tanks under frequent and rare earthquakes.Finally,Compare the effects of multi-directional earth-quakes and storage fluid viscosity on ground motion responses.Research shows:1.The modal frequency of the large vertical cylindrical oil storage tank is dense,and its first-order natural vibration period is 0.665s.The rigidity of the storage tank is greater in the aneroid state,and the period of the tank body decreases slowly with the increase of the mod-al order.2.Under the action of frequent earthquakes,the bottom of the tank wall is greatly af-fected by the bottom of the tank.In the case of different storage heights,in the fluid-solid coupling area,the equivalent stress increases with the increase of the storage depth,and the force on the connection part between the tank bottom plate and the tank wall is complicated.During an earthquake,the area with greater stress is located in the middle and lower part of the tank wall3.Liquid storage sloshing is an important factor in the lift-off phenomenon.The maxi-mum lift-off height of the full-liquid storage tank under the action of the X-direction El-Centro wave is 56.87mm;The larger the tank’s own weight,the less likely it is to slip.The sliding displacement of the full-liquid storage tank is about 1/22 of that of the empty tank.4.The equivalent stress value of the tank wall under rare earthquakes is larger than that under frequent earthquakes.The tank wall at the height of 1/8 wall buckled first.After the internal force is redistributed,the position of the maximum equivalent stress is lowered than that of frequent earthquake..