Deep beam theory
Deep beam theory
(OP)
OK guys here is a real test. When analyzing a pulley sideplate it occurred to me that the behavior of it was analogous to a cantilever deep beam. That being so I pulled out the handy dandy roark's and found that there is a considerable stess increase (on the order of 6-10 times) depending on the geometry. It then occurred to me that this would also apply to shear tabs as well. This makes shear tabs get fairly thick or long. It seems that there is a flaw in my logic, but I'm not sure where.
Any ideas?
Jeremiah
Any ideas?
Jeremiah






RE: Deep beam theory
DaveAtkins
RE: Deep beam theory
RE: Deep beam theory
So there must be a point where even deep beam stops being a depp beam and becomes shear tab. I have myself never checked it and shooting straight from the hip.
RE: Deep beam theory
I think DaveAtkins is talking more about clip angles being used as a type of shear tab. Typically, clip angle shear tabs are not welded along the top, making them "flexible". In other words, they may rotate slightly to alleviate transferring moment due to the connection to the supporting beam. Plate shear tabs are typically "semi-rigid". Some moment will be transferred.
RE: Deep beam theory
I looked that up, those give me my allowable stresses based on limiting the failure mode to plate buckling. That does not affect my calculation of the actual stresses (which is what Roark's gives) I'm still left, according to Roark's with a 6 to 10 times increase in actual bending stresses due to "deep beam theory"
RE: Deep beam theory
DaveAtkins