Stress Analysis Of Arch Structure Of Large LNG Storage Tank

As a clean and efficient energy, Natural gas (NG) is more favour in many countries around the world. Liquefied natural gas (LNG) provides some advantages for long distance transportation, and storage of natural gas. The production and trade of LNG has become a key factor that influences the pattern of supply and demand of natural gas in the world. As the rapid development of the world LNG industry, each tache of LNG industry chain got much great progress. And LNG receiving terminals have been built in coast to receive imported LNG from abroad. LNG tank is the main equipment of LNG terminal. The normal operation of the storage tanks is the key to keep the whole LNG terminal and trunk line well. Therefore, the development of large LNG storage tanks is a key problem to be solved for LNG industry. At the same time, as the development of large storage tanks, a series of new problems about design, manufacture and use are put forward. Especially with the increase of tank diameter, the deformation, strength and stability of vault grid structure are causing the attention of people. This paper mainly studied the deformation and stress conditions of large LNG storage vault structure under six different load combinations, and made a simulation analysis. The strength and stability must satisfy the requirements of specification.Firstly the article introduces the properties and the development condition of LNG in China and abroad, as well as the vault structure of LNG tanks and its research situation. Secondly, the finite element method and the application of MIDAS GEN software in the vault structural analysis are also introduced. Finally, taking 6000m3 LNG storage tank with dome structure as a study object and using of MIDAS GEN software, the deformation and stress of vault structure are simulated under five different load combinations of such constant load, live load, wind load, snow load, and seismic load. The buckling analysis was also completed to raise the stability. In order to validate the integral seismic performance, the analysis of response spectrum was applied. And on this basis, according to GB50017-2003 design of steel structures, software was used to check steel structure, while the strength and stability of the vault was checked. The analysis shows that the strength and stability of tank vault fully comply with the design specification.