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Strand7 Bending Moment Sign Convention

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BendingMoment123

Structural
Joined
Apr 1, 2020
Messages
25
Location
ZA
Hi, what direction (clockwise or counter-clockwise) are the positive and negative bending moment values found in the results tables. Results are based on the global axes.
 
I’ve never thought about the sign.

I always just look at the bending diagram, which is drawn on the tension side.
 
Its just that I'm reading reactions from nodes on plates. so it's a bit tricky to determine what is actually happening.
 
I'm not familiar with the software. If you run a simple structure, such as a beam fixed both ends, it should be possible to figure out the sign convention used.

BA
 
I use the international convention... an orthogonal right hand coordinate system with the (force direction signs) X (sign values for the face the forces are acting on).

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik
 
You aren't the only one who finds these things confusing. The diagram below is helpful. It is from the Rel 3 help, but the same applies to previous versions:

Plate_bending_conventions_yqhwpj.png


But rather than worrying about clockwise or anti-clockwise, I recommend displaying the plates as solids, then displaying surface stress values, so you can see which face is in tension.

Doug Jenkins
Interactive Design Services
 
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