Rectangular Underground Steel Shelter
Rectangular Underground Steel Shelter
(OP)
I have steel tank that is made of a 12 gage steel. I am trying to understand how to design this. Do I use thin plate theory with three sides simply supported or is FEA the way to go? If FEA, then is STAAD or any other software capable of doing the same?






RE: Rectangular Underground Steel Shelter
RE: Rectangular Underground Steel Shelter
Use reinforced concrete for your shelter.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Rectangular Underground Steel Shelter
12 gauge is not much thicker than a highway sign - only .105''
RE: Rectangular Underground Steel Shelter
Not all underground storage tanks are concrete: fuel tanks are steel and I've seen stainless steel water tanks, small ones. We need more information on your question.
There are days when I wake up feeling like the dumbest man on the planet, then there are days when I confirm it.
RE: Rectangular Underground Steel Shelter
RE: Rectangular Underground Steel Shelter
RE: Rectangular Underground Steel Shelter
This is a feasibility study. Our client has asked us to look at the possibility of use of 12 gage steel (he has that in surplus). He got the idea from a storm shelter he saw in Europe. He wants to look at possible height, length and depth combinations that we could use to do the same.
We have already informed him that it might not work. But, I wanted to make sure that I approach this correctly.
I think I have figured out how to design it against floatation. I am was planning to add concrete strips at the bottom. (like a manhole with an extended base). Rebar could be welded to the sides of the tank so that the concrete and the tank are together. The client is fine with that.
The one size he wants us to look at is 48" deep by 72" long by 36" wide. I might be able to persuade him to use stiffeners.
We are looking to design it for soil pressures.I was planning to use an active soil pressure of 60 pcf. If you need anything more let me know
RE: Rectangular Underground Steel Shelter
Is this for a bunch of midgets or just one or two hunched over people??
RE: Rectangular Underground Steel Shelter
RE: Rectangular Underground Steel Shelter
It can certainly be done, you've just got a number of challenges to work around given the material constraint.
If this is a storm shelter, do you need to calc in additional loads (ie:falling debris) or plan for water issues, as well?
I've seen people build bomb shelters and storm shelters out of corrugated culvert piping, with reasonably satisfactory results.
Good luck.
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Rectangular Underground Steel Shelter
Second, you'll need to investigate the lateral effects on your plate. I don't see how you can design this with out stiffeners. I saw test results on a similar type structure,but above ground. The whole thing was double walled with steel channels. The lab that tested it highly recommended hearing protection, go figure. AISC 13th, chapter B4 will give you a guideline for stiffened elements and effective width.
I always find it interesting how the average joe preceives how we design structures. Putting a steel box in the ground is just as complicated as having it above ground.
There are days when I wake up feeling like the dumbest man on the planet, then there are days when I confirm it.
RE: Rectangular Underground Steel Shelter
How do you break out if the door gets jammed??
RE: Rectangular Underground Steel Shelter
There are days when I wake up feeling like the dumbest man on the planet, then there are days when I confirm it.
RE: Rectangular Underground Steel Shelter
I still trying to look at resources that could design the plates.
RE: Rectangular Underground Steel Shelter
By the time you add all the steel necessary to make 12ga work, supports at 4" o.c. or whatever, it will cost about 10k to fabricate... They sell these pre-cast, reinforced concrete bomb/storm shelters (MS squared said it first) for a fraction of the cost since they are glorified box culverts and can be cast in those types of plants (google it, you'll see they are all over). Pretty easy to make 8-12" of reinforced concrete meet your bending stress and impact resistance requirements.
RE: Rectangular Underground Steel Shelter
He is a long time client and this economy we just dont want to displease him. If I can figure out a methodology to show it does/does not work I think we will be good. I trying to get in grips with what method should I adopt to actually design it.
RE: Rectangular Underground Steel Shelter
RE: Rectangular Underground Steel Shelter
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Rectangular Underground Steel Shelter
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/