The Study About The Wind-induced Of The Large Steel Tanks

Large steel storage tanks are important equipment in the petroleum industry.Most of them have been built in coastal areas,and they are wind sensitive structures.When empty tanks or liquid reservoirs are short,they are prone to instability and destruction under the action of wind load,causing huge economic losses and environmental pollution.At present,most wind-induced buckling studies mainly focus on medium and small storage tanks,which are rarely involved in large variable thickness steel storage tanks.In this paper,the wind load and wind-induced buckling behavior of the large steel tank represented by 150,000 square tanks are studied,the results of this study are valuable for the design of large steel storage tanks.The thesis is divided into six parts;(1)The background and significance of wind-induced buckling of large storage tanks and the development trend of storage tanks are described.The current situation of wind-induced buckling of large storage tanks at home and abroad is summarized,and the wind load of storage tanks is summarized in the wind field research method and current design specification.Present problems in current research is put forward,and the research content and technical route of the thesis are pointed out.(2)Analysis of non-stationary wind velocity around large storage tanks.The steady pulsation wind speed was synthesized by harmonic superposition.Using the method of wavelet transform to synthesize seismic wave,the time-varying power spectrum suitable for non-stationary wind field is deduced,and its validity is verified.Based on the steady wind speed,the unsteady pulsation wind speed is synthesized,which provides accurate wind speed data for wind load analysis.Based on the steady wind speed,the unsteady pulsation wind speed is synthesized,which provides accurate wind speed data for wind load analysis.(3)Study on the surf'ace wind load characteristics of' large storage tank.The influence of different f'actors oin the wind load characteristics of inner and outer surface of tank was analyzed,the air pressure distribution of' the reservoir surface was obtained.The approximate fonnula of-body mass coefficient suitable for large storage tank is fittecd,which provides reference for large storage tank design.(4)Analysis of static wind buckling iin large storage tanks.The eigenvalue buckling behavior of three types of air pressure models(whole,uniform and local)was compared,the wind loading area of the main control tank is obtained.The influence of unifonn defects on the wind induced static buckling performance of storage tanks is discussed which set a f-oundation for the study of' wind vibration buckling in large steel storage tanks.(5)Analysis on the buckling of large storage tanks.The effect of unifori defects on the buckling of large steel storage tanks was studied,thcen buckling behavior of storage tanks under static wind and gusty wind was compared,from which we obtain the importance of pulsating wind effect in the design of air resistance of storage tank.(6)Discussion on design of large storage tank against wind is put forward.This paper analyzes the strengthening mechanism and damage characteristics of wind resistance structure in large steel storage tanks from three aspects:curb angles,stiffening rings and strengthening ring.The differences of the design norms of wind resistance are discussed.The wind-induced buckling properties of the storage tank after adopting wind resistance design are analyzed.It provides reference and suggestion for the design of large storage tank wind resistance.