Seismic Response Analysis Of Large Vertical Liquid Storage Tank

Vertical storage tanks are one of the important facilities in the oil storage process.With the rapid development of current economy of China,the application of liquid storage tanks in petroleum and chemical enterprises is becoming more and more extensive.For it is used to store various dangerous chemicals such as oil,the destruction of vertical liquid storage tanks may not only cause direct losses for petroleum and chemical enterprises,but also could cause larger and stronger secondary disasters,thus the research of safety performance of tanks has been highly valued by many scholars.At present,the development of oil storage tanks is becoming thinner wall,foundation floating and larger size.Most of the large oil storage tanks are external floating roof storage tanks,and the entire structure directly set on the foundation.Although this design method greatly reduces the manufacturing cost,it is easy to cause various damages under earthquake.Thus in-depth study of the seismic dynamic response of large vertical floating roof tanks is of great importance to ensure the safe operation of these tanks during their application.In this paper,by using the large-scale finite element numerical simulation software ADINA,based on the modal analysis,considering the fluid-structure coupling effect between the structure and the liquid,the seismic response analysis of the simplified model of the large vertical thin-walled cylindrical liquid storage tank is carried out.The analysis of research work mainly includes the following aspects:1.The research of scholars in China and abroad is summarized,the work progress and research results of the simplified model,numerical simulation research,experimental research and normative standards of the oil storage tank are summarized,and some problems that haven’t been solved are pointed out;2.The finite element model of large vertical cylindrical liquid storage tank with a maximum capacity of 150,000 m~3 was established and the characteristics of liquid sloshing mode and fluid-structure coupling mode were analyzed.The influence of different liquid height and liquid density on the natural frequency of liquid storage tank was studied;3.The seismic response analysis of the anchored liquid storage tank was carried out to study the fluctuation of the liquid surface sloshing wave height,the dynamic response of the tank wall and the force of the bottom under the horizontal earthquake,horizontal and vertical earthquakes.The reliability of the calculated results is verified by comparison with the calculated results in the specification,and the area where the liquid storage tank may be buckled and damaged is obtained;4.The seismic response analysis of the unanchored tank was carried out to study the response of the sloshing wave height,the displacement of the tank wall,the stress change and the lift-up of the bottom of the tank under the horizontal earthquake,horizontal and vertical earthquakes.By comparing with the results of the anchored tank,the damage area that may occur in the unanchored tank and the lift-up form of the bottom of the tank are obtained.