Thanks for showing that example hardbutmild. That confirms my understanding that ultimate moment is higher than yield moment but not much higher. I wonder if there was a generic way to prove that is always true. That would put this to bed in my mind.
BridgeSmith, how can yield be considered...
Yes, first yield occurs at the face of the column. But the yield moment is lower than the ultimate moment, because after the steel yields the neutral axis can be pushed up and the curvature increased until the concrete crushes.
That means that when the face of the support reaches the ultimate...
Your premise agrees largely with what I’ve read on this issue.
My understanding is that bar development is required to preclude splitting or bond failure in the concrete which is a brittle mode of failure, in lieu of yield which is ductile. So this has nothing to do with actual rupture of the...
That’s only true if the section is designed for the balanced condition, or it’s compression controlled. In this example the footing is tension controlled, which means the strain at PhiMn is greater than the yield strain plus 0.002.
So no, the steel will absolutely yield prior to the factored...
I'm stuck on a thought experiment regarding development length and I'm wondering if I can get some guidance.
Consider a simple column footing. Assume that the moment at the critical section, Mu, is exactly equal to φMn. Also, assume that the footing section is tension-controlled.
It follows...
