Peak Load of an Assembly?
Peak Load of an Assembly?
(OP)
Hi all,
I'd like to use FEA as a way to predict the maximum download a structural assembly can take before failure. In our lab, we build setups that involve steel beams, connectors, and bolts. We apply a download to an area of the assembly, and we monitor load vs. crosshead displacement. Eventually, the assembly will reach some peak load and buckle and begin to lose load. Is there a way that I can use FEA to predict this peak load? For example, if we test an assembly and the peak load is 50 kips, I'd like to build this model in CAD and test in FEA to determine the theoretical 'peak load'.
I'm currently running Autodesk Simulation Mechanical 2014 through the non-linear mechanical event solver.
Any tricks or ideas to determine this?
Thanks,
M
I'd like to use FEA as a way to predict the maximum download a structural assembly can take before failure. In our lab, we build setups that involve steel beams, connectors, and bolts. We apply a download to an area of the assembly, and we monitor load vs. crosshead displacement. Eventually, the assembly will reach some peak load and buckle and begin to lose load. Is there a way that I can use FEA to predict this peak load? For example, if we test an assembly and the peak load is 50 kips, I'd like to build this model in CAD and test in FEA to determine the theoretical 'peak load'.
I'm currently running Autodesk Simulation Mechanical 2014 through the non-linear mechanical event solver.
Any tricks or ideas to determine this?
Thanks,
M





RE: Peak Load of an Assembly?
This is an intensive process, requiring a strong computer and days to weeks of analysis depending on debugging of the model and such. Simple hand calculations may serve a good purpose to get an idea.
RE: Peak Load of an Assembly?
While that would probably give me an extremely accurate result, I was hoping for something a little quicker in terms of analysis time.
My question was actually a little more basic as I am relatively new to FEA. For example, when I run my assembly now all I'm getting is displacement, von mises stress/strain, or max principal strain in the results. If I apply a load that is 10x what the assembly should take to fail (compared to test results), it will just show an extremely high stress value like 1 million ksi Von Mises stress, which isn't practical.
If I just take a standard steel bar that is 0.25" in diameter and constrain both ends and apply a download (to simulate a 3 point bend test), the bar should bend until some peak load is reached and then it will to continue to yield and not hold this peak load any longer. Is there a way to determine this peak load?
RE: Peak Load of an Assembly?
RE: Peak Load of an Assembly?
RE: Peak Load of an Assembly?
The way you might get what you want is to figure out from the buckling mode shape where to apply an initiator load on a non-linear analysis, which will induce a failure when appropriate. This is not a simple type of analysis, and there is no way that I know that will make it fast or easy to do.