Support Design For Skirted Cone Bottom Tank 3

[merton]

API 12F shows a diagram for support of a skirted cone botton, but does not go into detail regarding how to size the support rings.
I also have a tank design program at work which will give design thickesses for a cone bottom based upon cone slope, size of tank and internal pressures. This design is based upon the cone being supported by an earthen foundation and not a steel skirted cone bottom.

If anyone has suggestions as to how to determine the number of and thickness of supports for a skirted cone bottom tank I would appreciate it. For reference, the largest diameter tank our facility produces is 23'-6".

 

[JStephen]

You can check the design of the cone bottom and the compression ring region using the rules in API-620.

The skirt itself can be designed by rules in API-620 or elsewhere. Basically, the skirt is designed as a short beam, with stress = P/A + MC/I. The missing part that you need is allowable stress for a thin cylinder. That can be found in API-620 as well as AWWA D100. AISC ASD also includes compressive stress within certain limits.