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Unread 13-05-2008, 11:04
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AKA: Mark Kramarczyk
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Re: pic: Beam Bending Example

Quote:
Originally Posted by kramarczyk View Post
I used the left vertical edges as my constraints and fixed them only in two dimensions... on the axis parallel to the load, and on the axis that is both perpendicular to both the load and the axis of the beam. They were left free on the axis that would allow them to get closer to each other.
Clarification... "One was left free on the axis that would allow them to get closer to each other, the other was fixed on this axis." Leaving both free causes the software to attach weak springs to contain that degree of freedom which is a bad habit to get into. I also failed to mention that I'm using 1000 lbf uniformly distributed loads as I look at these beams. It's a completely ficticious load, but since we're only looking at how the beams carry the loads and not the absolute magnitudes I don't see an issue.

Attached is the deflection diagram that goes with the original post...
3.475 lbm
8643 psi max stress
.133 in max deflection
Attached Thumbnails
Click image for larger version

Name:	Beam Bending-def.jpg
Views:	69
Size:	37.9 KB
ID:	6645  Click image for larger version

Name:	Beam Bending-stress.jpg
Views:	68
Size:	42.6 KB
ID:	6646  
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Last edited by kramarczyk : 13-05-2008 at 16:26.