Finite Element Force Analysis Of Four-circle Tangent Steel Plate-concrete Underground Oil Tank

China has a large population and a large demand for edible oil,and oil storage become a crucial link.Oil storage of low temperature is an important ecological oil storage technology which can prevent and slow down the deterioration of oil quality.The underground oil tank has the characteristics of low temperature,avoid light and low oxygen concentration,which can prolong the shelf life of oil,prevent the substantial loss of nutrients in oil,reduce the harm to the safety and quality of edible oil and save ground land resources.However,underground oil tanks has problems such as waterproof,moistureproof,and complex stress.For this reason,a four-circle tangent steel plate-concrete underground oil tank was proposed.The underground oil tank is mainly composed of internalinternal steel plate,reinforced concrete.And the internalinternal steel plate can be used for waterproofing.In this paper,the mechanical properties of four-circle tangent steel plate-concrete underground oil tank was studied by the combination of field full-scale test and finite element analysis.The main research contents and results of this paper are as follows:(1)Based on the field full-scale underground oil tank,the finite element model of four-circle tangent steel plate-concrete underground oil tank was established by ABAQUS.The stress of circumferential reinforcement and vertical reinforcement of underground oil tank wall under soil pressure was simulated and analyzed.The reinforcement in the finite element model adopts truss element,the internal steel plate adopts shell element,and the concrete adopts solid element.The reinforcement is embedded in the concrete tank wall,and the internal steel plate is attached to the internal of oil tank wall.(2)The field test of four-circle steel plate-concrete underground oil tank was carried out.The arrangement scheme of measuring points was formulated,and the steel bar dynamometer and earth pressure gauge of underground oil tank wall were installed.The stress and earth pressure of steel bar under earth pressure were measured.Compare the results between the experimental and finite element calculation,the reliability of the model was verified.(3)Based on the verified finite element model of four-circle steel plate-concrete underground oil tank,the parametric analysis of the oil tank wall force was carried out.The design parameters mainly consider the height of oil tank wall,diameter of ring reinforcement,spacing of vertical reinforcement and concrete strength grade.The heights were 4 m,10 m,15 m and 20 m,respectively;the diameters of ring bars were 12 mm,14 mm,16 mm and 18 mm,respectively;the spacings of vertical bars were 100 mm,150 mm and 200 mm,respectively;and the concrete strength grades were C30,C40 and C50,respectively.The results show,when the height of the oil tank wall was 4 meters,the vertical reinforcement bearing the main force,and when the height of the tank wall reached 10 meters,the circumferential reinforcement bearing the main force.The modification of reinforcement ratio and concrete grade has little effect on the stress distribution of underground oil tank wall.