Bearing Plate
Bearing Plate
(OP)
I have a bearing plate design example that I follow. I often come up with plate thicknesses exceeding 1", as a result of both the load and the beam shape "k1" value.
If the flange width of the beam exceeds the maximum possible plate width, I see no reason to have the plate thickness exceed 3/8" or just enough to have threaded anchors shop welded to the top, since there will be no cantilever bending.
What are your thoughts?
Thank you!
If the flange width of the beam exceeds the maximum possible plate width, I see no reason to have the plate thickness exceed 3/8" or just enough to have threaded anchors shop welded to the top, since there will be no cantilever bending.
What are your thoughts?
Thank you!






RE: Bearing Plate
MBones
RE: Bearing Plate
MikeHydroPhys
mdshydroplane
RE: Bearing Plate
I assume you are referring to a beam bearing on CMU but I suppose concrete would not be any different. A 1" thick bearing plate may seem thick but if you have a beam with a large reaction bearing on CMU it is not uncommon to have a plate 1" thick, or more.
When you say there is no cantilever I assume you mean there is no cantilever if the bearing plate does not extend past the beam flange, that is only true if you consider the beam flange as distributing the load to the CMU. If you did that you would have to check bending in the beam flange from "k1" to the edge of the flange. I believe this is allowed but in most cases I doubt the flange would be thick enough to resist the bending moment.
RE: Bearing Plate
I size my bearing plates with at least 2" extra width on each side of the beam flange so that if there is a slight problem with getting the bearing plate in the right position, the beam will still land on the plate. For example, if I have a beam with a 6" flange, I would design a 10" wide bearing plate to accomodate the beam....that way I've accomodated slight errors and misalignments.
RE: Bearing Plate
RE: Bearing Plate
The allowable bearing stress exceeds the applied. And the beam is fastened with 0.75" diameter threaded rod anchors shop welded to the top of the bearing plate.
This current situation is taken care of.
For future reference, if my bearing plate is cast into reinforced, poured concrete or reinforced concrete masonry, if the vertical steel reinforcing proves to support the axial load, would the vertical steel reinforcing supersede the need to consider allowable stress on the cemetitious material, thus allow to neglect or ignore any "required" thickness of the plate?
Thank you!