3 Replies Latest reply on Mar 13, 2015 4:39 PM by Mike Pogue

    FEA: Newbie Help

    Brent Theobald

      I am trying to check someone's work.

       

      Can someone share how to set up an FEA study for this simple part? (Maybe it isn't as easy as I think?)

       

      I am trying to validate the force needed for a leg to fail under these conditions.

       

      It has 750 pounds of downforce. The top plane should be restrained. How much force would be needed to have the weld joints fail?

       

      I have attached a file if that helps.

       

      Any help is greatly appreciated.

       

      Leg.JPG

        • Re: FEA: Newbie Help
          Mike Pogue

          You are going to get much better results with a hand calc out of Shigleys for a welded joint in pure shear. Get the allowables from AISC 360 if it's in fatigue.

          • Re: FEA: Newbie Help
            Jared Conway

            "check someone's work"

             

            what have they provided you with? fea or hand calc?

             

            what is your concern with their work?

             

            the reason i ask is like mike pointed out, analyzing a weld is challenging with fea. especially because i think where you're pointing at for a "weld" might be a singularity.

             

            but some basics

            sim pro > weld connector

            or model the welds and use solids

            the lower restraint will be challenging but a normal to restraint should be a good start

            force on the top should be just a simple force

            • Re: FEA: Newbie Help
              Mike Pogue

              Yeah, I could have been more clear. Analyzing welds in FEA is a pretty sophisticated task. If you are not confident that you understand the pitfalls, I would not deliver that analysis. You are on much more solid ground with handbook type calcs. Also, the case you have presented is very simple. I can see a lot of disadvantages but few advantages to going to FEA for this.