Rectangular Tank Top Edge Stiffening

[mmaurigi]

Can someone explain the process for calculating the size of a top edge stiffener on an open top rectangular tank subject to hydrostatic pressure.

Thanks

 

[rb1957]

i asume that you mean a tank holding water (or fluid) ... then the stiffener provides bending stiffness for the tank face ... a plain flat sheet is going deflect significantly out-of-plane. so then it sounds like a beam with a running load that's constant (well almost, i guess) ... and the four sides of the face react the out-of-plane pressure load (don't forget there's a component of load form the other faces too). i'd suspect that the upper edge would react about 1/2 the lower edge reaction (just by considering the triangluar loading from the fluid) and the side edges would also support some of the load (depending on the geometry of the face.

 

[dvd]

Design of Weldments by Omer Blodgett has a nice treatment of tanks and stiffening.

https://ssl.lincolnelectric.com/foundation/item.asp?prodnum=DW&PID=16

 

[BarryEng]

Do a google of this site (top of this page) for 'rectangular tanks' for many threads. I think that some of them also addressed top edge stiffening.

 

[jte]

mmaurigi-

I will second dvd's recommendation to get Mr. Blodgett's Design of Weldments. However, if you are willing to pay the equivalent of a cheap lunch more, I'd recommend Mr. Blodgett's Design of Welded Structures instead.

https://ssl.lincolnelectric.com/foundation/item.asp?prodnum=DWS&PID=16

It covers a bit more ground. However, the rectangular stiffened tank parts are identical at least for the first three pages (part 4.6 in Weldments, part 6.5 in Welded Structures. The bottom line is that either of these books could easily be sold for nearly 10x their price and still be a decent value. At the current asking price, they are a ridiculously good bargain, written with a good combination of simplicity and thoroughness for the Bachelor's level engineer.

jt