Structural Stress Analysis And Weak-Proof Structure Appraisal For Vertical Vaulted Storage Tanks From 10~3 To 10~4 Cubic Meters

In petrochemical industry has developed rapidly today, the world have been built quite a number of oil tanks, the importance of the security issues increasing. In our oil and chemicals industry, vertical tank was a widely used form. Once the devices accidents, the consequences would be unthinkable. So in engineering, we usually design the roof for a weak one, to enable when tank have an extremely pressing circumstances, roof-to-shell first broken to avoid going to bring more secondary disasters. Many experts generally believed that the roof of cone tank formed compressive region, and have weak head protection effect. And because of a self-limited of the dome tank have not the effect of protecting the weak. Dome tank is an extensive use of forms, therefore, research of the tank security is very important.This paper to 1×10~3m~3,3×10~3m~3,5×10~3m~3 and 1×10~4m~3 four different dimensions vertical dome tanks for studying, and to the three design standards of tank design: API650,GB50341 and SH3046 for research,design the weak roof tank accord with standards, according to the three standards of weak connection definition to determine whether to meet the conditions of weak roof. Then using numerical simulation technology of the finite element analyse the strength, stability and post-buckling of tanks. This paper established the element analysis model of the strength, stability and post-buckling four different dimensions tanks. The same volume tank based on three standard design, the destruction pressure of the roof-to-shell and bottom-to-shell,the coefficient of weak roof strength ratio,lift-off radius and height are basically the same. The performance of three design standard tank weak structure is less affected. As tank volume increased, the roof weak was enhanced. The unstability pressure a far greater than its destruction pressure, and strength of the damage occured before destruction damage. The breakdown pressure of after buckling is less than before buckling. For the four dimensions tank designed weak roof, researching the roof radius and the height of roof-to-shell connection weld. Consequence state clearly increasing the radius of the roof or reducing the weld height that can accomplish the weak roof design.