Research On Base Isolation Of Vertical Storage Tank With Bi-directional Earthquake Action

With the rapid development of economy in China and increasing dependence on energy, there are more and more needs of oil and natural gas gradually, especially oil. In order to build the system of oil and production capacity reserve to achieve long term goals of our strategic petroleum reserve, it is an inevitable trend to build a large storage facility. Vertical storage tanks are storage facilities which are widely used in petroleum industry, petrochemical and related enterprise. Because of the flammability and explosive, once is the storage tanks damaged in the earthquake, the effect of disasters is critical, and at the same time it is prone to serious secondary disaster such as fire and environmental pollution etc., which may cause serious effects to ecological environment.The theory of base isolation is introduced in this thesis and the base isolation basic theory of vertical storage tanks is deduced, seismic response of base isolation vertical storage tanks under the bi-directional is studied and parameter effect of base isolation is analyzed. Main research content is as follows:1. The evolution of conventional seismic and insufficient is summarized and the primary method and research progress of vibration control of structure are introduced. The basic development history of isolation is introduced and the classification is introduced, characteristics of base isolation and research are summarized. It focuses on the research progress of tanks seismic and isolation at home and abroad.2. Base on the theory of fluid dynamics and structural dynamics, tanks liquid motion is divided into sloshing, fluid-solid coupled motion and rigid motion. Taking into account of the fluid-solid coupled vibration effect to sloshing component, the basic motion equation of tanks base isolation is deduced and the validity of the theory is verified.3. Considering the coupled action of non-linear restoring force of lead rubber bearing under bi-directional earthquake, the motion equation is established and the seismic response of the vertical storage tanks is computed. Comparing with non-coupled conditions, it is concluded that the effect of seismic response of coupled action is slightly smaller.4. Motion equation of base sliding isolation tanks is established under single and bi-directional earthquake action. Seismic response of three typical height to diameter tanks is analyzed, it is concluded that the effect of seismic response of bi-directional earthquake action is slightly smaller.5. The seismic response property of lead rubber bearing base isolation tanks is researched under the influence of seismic intensity scale, site conditions, isolation period, damping ratio, height to diameter and other factors. It is also researched the seismic response property of base sliding isolation tanks under the influence of peak acceleration, friction coefficient, site categories and other factors. Through the study of two kinds of base isolation, variation rule of base shear, overturning moment and sloshing wave is given, which provides reference to base isolation design of vertical steel storage tanks.The results of research in this paper are summarized and the further research in depth content closely related to the work of this paper is proposed.