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Calculating max load of storm shelter

  1. Sep 15, 2011 #1
    Easy question

    Have a 5ft x 5ft x 5ft structure made from 3/8 carbon steel AISI 1018 I think

    What is the max load this thing can take? What's the formula?



    Do I use the Modulus of Rigidity? Elasticity? Where can I find these values?

  2. jcsd
  3. Sep 16, 2011 #2
    It's just a box? No, you can't just use sig=F/A...that is for loads on a surface. For structural integrity you have to get into a bit more work. Especially if it is a frame
  4. Sep 16, 2011 #3
    Yes it's just a box

    3/8" Steel welded up to connect the walls

    Any suggestions where I can find the correct formulas?

    Been a while since college and cant remember where all that stuff is

  5. Sep 22, 2011 #4
    I think you should put some figure how you apply the load, is it bending, torsion, tension or compress. Different situation will have different formula.
  6. Sep 23, 2011 #5
    My suggestion. Overbuild. Don't worry too much about the load calcs. If it is well built and overbuilt, you should have no worries. I doubt you are going to settle for a 20% factor of safety, so why not reinforce all the walls and ceiling and gusset your corners and make that baby unbreakable?
  7. Sep 27, 2011 #6


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    rimmer2300: There is not really an easy formula. I assumed there is a compressive load, P, evenly distributed over the top surface of the box. I currently got a maximum allowable load of P = 80.9 kN. Therefore, it currently appears the box will resist a compressive load of at least 80.9 kN.
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