Research On Seismic Response Of Parallel-isolated Isolated Tanks With Ring Beam Foundation

The current world is consuming a lot of energy every day,especially with the development of the national economy,the consumption of oil resources is increasing day by day.However,several serious oil crises broke out in the world in the twentieth century,which not only brought great trouble to the life of the people,but also seriously hindered the development of the national economy.How to efficiently store oil resources plays a vital role in the life of the people and the development of the country.The storage tank acts as an efficient storage container,is widely used in the field of petrochemical industry.Most of the storage media are flammable and explosive.Once destroyed in the earthquake,they will cause serious consequences,causing fires,damaging the environment,endangering human health and immeasurable loss to the country.In the event of an earthquake,how to effectively reduce the seismic response of the tank and ensure the safe use of the storage tank is the purpose of the unremitting efforts of the researchers at home and abroad.In view of this,this paper is on the existing research achievements of storage tank isolation at home and abroad and under the support of the National Natural Science Foundation Project of large vertical storage tank near fault long period and long pulse earthquake shock absorption control(51478090).A new type of parallel isolation device applied to large vertical storage tanks is put forward,which makes the ring beam rolling isolation and the friction sliding and friction isolation of rubber particles as the raw materials in parallel.First,the best ratio of sliding friction material applied to the isolation layer is obtained through shear test.Then,the ADINA finite element numerical analysis is applied to study the seismic response of the storage tank with parallel isolation device,and the shaking table test of the parallel isolation vertical storage tank is carried out.The research has been carried out from the following aspects:(1)The research progress on aseismic and isolation of storage tanks at home and abroad is summarized,and the research progress of self reset isolation system and sand cushion isolation system is introduced.(2)This chapter of the sand-rubber particle composite material as the principle of isolation layer was analyzed,the composite isolation cushion shear test of sand particle diameter,vertical pressure force and influence of the ratio of sand in the mixture on the mechanical properties of the composite isolation layer,the optimal proportion of the sliding material used in the isolation layer.The results show that: When the sand selection of large size sand,composite materials applied in the upper part of the vertical compressive stress increases,the shear strength of the composite material;when the sand is fine sand or sand,sand accounted for 75%,the composite shear strength increases;when the sand grit,sand for 100%,composite shear strength increases;when the composite rubber particles accounted for 100%,the weakest shear properties of composite materials resisting device,the equivalent stiffness of the minimum,at this time for the sliding material optimal ratio.(3)A finite element model of a parallel isolation tank and a non-isolated storage tank is established by ADINA finite element software.The damping effect is analyzed under the action of EL-Centro wave of 0.2g,and the mean effect analysis of 7 seismic waves is carried out.The results prove that the parallel isolation device,control of seismic response significantly,compared with the non-isolated storage tank,storage tank,tank base moment and base shear wall stress and wall acceleration and dynamic fluid pressure decreases,and the liquid sloshing wave height is not obvious in the control of the tank;seismic response analysis several seismic waves,should mean effect analysis and selection,should be careful to select larger deviation from the mean seismic wave.(4)A parallel isolation device is designed.The scale of 1000m3 storage tank is scaled according to 1:4 ratio.The shaking table test of parallel isolation vertical storage tank is carried out,and compared with non-isolated storage tank,the damping effect of isolation tank is given.The test results show that after the parallel use of the sliding isolation device and the sliding isolation device with rubber particles as the friction and sliding material,the tank's ground motion response decreases,and the acceleration of tank wall decreases,and the lifting phenomenon of the tank wall can not be effectively controlled.