overturning stability of rectangular tank with 4 legs 1

[mohammad1367]

Hello every body,

Does anybody know how to investigate overturning stability of rectangular tank which is mounted on the ground with 4 legs?

BR.

 

[jte]

Yes, I do.

I'll recommend that you contact a third year mechanical engineering student. Or second year... in many parts of the world they should be half way thru the second year and have a course called "Statics" under their belt.

 

[mohammad1367]

Thank you very much!

It is not as simple as you think.

Refering to EN14015, Section 12, you can find some complicated formula for tank with circular cross section.

Check the attachment please

 

[jte]

That's swell. But I was somehow under the impression that you had an issue with a rectangular tank on four legs. Either way, statics must be satisfied. The calculation sheet which you attached walks through developing forces and moments. When the applied loads exceed those which keep the tank stabile, bad things happen.

Based on your other posts, you appear to be attempting to do something with little experience, no in-house oversight, and a severe dependence on the internet for your consulting. For example, two months ago you asked essentially the same question in thread507-399609. The work you are attempting to perform can put people in harm's way. It seems that you are operating outside of your area of competency, keep in mind that this is one of the requirements which goes with offering mechanical engineering services as a PE. If this is some sort of senior project effort, let us know, because that's about the only excuse.

 

[LittleInch]

How do YOU think it should be done?

At its most basic this is simple moment diagram.

you find your forces (wind is probably the worst), work out the force from your design wind load (force on a bluff body) then work out the weight and a few assumptions and hey presto - it works or it doesn't work.

Tanks on legs will be much more prone to overturning than tanks sitting on a base as the C of G is much higher.

You probably also need to assume that the legs won't buckle before overturning, but that could be a big assumption.

All in all this seems a simple exercise.

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