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Hi Everybody.
Hope you can help me, as you have done times before.
My objective is to check, once I've reduced the thickness of the Basement (from 115 mm to 90 mm), how the stress values are (lower or higher, how much higher, etc) along the Basement with a lateral force of 1000 kN.
My structure is a Cast Iron Piece of 9000 kg aprox. with 8 holes, where the screw Connection is.
8 Screws M56X200 8.8 and Preload of 1097298 N
My question, once I know my OBJECTIVE, how should I simulate this?
I attached this file if anyone wants to try.
I don't know whether I have to use the Option "Fastener" (Redifine Model>Connections>Fasteners). Because in my case I don't know what should I do.
Solved! Go to Solution.
Hi David,
If you are not modeling the ground option 2 mentioned above is the best, because the shaft of the bolt holes are not conveying the force but the bolt head is pushing the plate to the ground.
But I would model the ground and include contact with the ground in this case, because the direction of your force will push the part into the ground. If there is no ground to push back you're simulation will show more deformation than is realistic.
I've made an example of how to model the fastener.
Benefits of using fastener instead of option 2 is what I mentioned above AND the fact that the preload is really applied previous to the other loads and not at the same time (option 2 is like bolting the part while it's already loaded, so if that is the case you should use option 2 or, not use 'account for stiffness' in the fastener.)
If you want to use the Fasteners you also need to model the counter-part.
With the stresses in the base plate as the objective, using fasteners is an appropriate method.
Do realize that friction is extremely simplified in the setup with fasteners using fixed separation, resulting in
a conservative simulation result; stresses in and around the bolt holes between baseplate and counterpart will be a bit higher than in reality
because there is no friction/contact force outside of the 'separation test diameter' circle.
Hi Agnes,
How can I set a fastener in this example? That is my Problem.
THanks,
David
Hi David,
If you are not modeling the ground option 2 mentioned above is the best, because the shaft of the bolt holes are not conveying the force but the bolt head is pushing the plate to the ground.
But I would model the ground and include contact with the ground in this case, because the direction of your force will push the part into the ground. If there is no ground to push back you're simulation will show more deformation than is realistic.
I've made an example of how to model the fastener.
Benefits of using fastener instead of option 2 is what I mentioned above AND the fact that the preload is really applied previous to the other loads and not at the same time (option 2 is like bolting the part while it's already loaded, so if that is the case you should use option 2 or, not use 'account for stiffness' in the fastener.)
Thanks a lot!!
That is exactly what I was looking for.