How is load transfered?
How is load transfered?
(OP)
Im wondering how is load stransfered here.
RC beam is partly integrated into RC slab. There is a bearing masonry wall on top of RC beam (over entire lenght of the beam). Since beam is almost 6 m in span, but distance from slab to wall is only 0,80 m, does that mean that load gets transfered through slab too since distance from beam to wall is short and loads always took the shortest path?
Im asking this because I get so much different results when calculating this as 2d problem in FEM software comparing to hand calculation where I only consider beam and a load on it.
RC beam is partly integrated into RC slab. There is a bearing masonry wall on top of RC beam (over entire lenght of the beam). Since beam is almost 6 m in span, but distance from slab to wall is only 0,80 m, does that mean that load gets transfered through slab too since distance from beam to wall is short and loads always took the shortest path?
Im asking this because I get so much different results when calculating this as 2d problem in FEM software comparing to hand calculation where I only consider beam and a load on it.






RE: How is load transfered?
Not sure of the construction of the bearing wall above, but the first and probably predominant load path would be the wall/beam transferring the load directly to the columns as a deep beam.
RE: How is load transfered?
RE: How is load transfered?
RE: How is load transfered?
tnx for helping
RE: How is load transfered?
RE: How is load transfered?
RE: How is load transfered?
RE: How is load transfered?
Never mind.
You helped.
TNX.
RE: How is load transfered?
RE: How is load transfered?
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: How is load transfered?
RE: How is load transfered?
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: How is load transfered?
'many ways go to Rome'
as we say in Germany :)
best regards
Klaus
RE: How is load transfered?
Dik
RE: How is load transfered?
RE: How is load transfered?
Actually load distributes to paths with greater stiffness.
Very likely not the case. There is no reason for trying to develop the top bars. It's hard (and pointless) to make that connection anything more than a hinge.
No, the slab cantilevers past the beam as can be seen in the plan and section.
n3jc,
Stick with designing the full load to the beam.
RE: How is load transfered?
As depicted, the slab is not a simple span, it is a propped cantilever.
RE: How is load transfered?
DETstru, yes, sorry meant more rigid path. Wording came out quite wrong!
Yes, if it is considered a hinge of course the load won't go there. I don't have all the details, just considering what OP said about load going to the wall, which would happen. Top bars will likely be hooked and developed. Depends on bar size, wall thickness.
Hokie66 & DETstru, Yes I see the slab cantilevers, but a cantilever is half a simple span, the easiest way to estimate if a cantilever will work. It depends on how stiff the wall and wall connection are.
Re-looking at the details, both the wall and the slab seem to be discontinuous at the intersection, so it may be quite flexible. In that case i would probably just ignore the wall as support, though theoretically it may take a good portion of the load.
RE: How is load transfered?
There is no point in trying to develop a truly fixed connection from slab to wall. It's difficult to do regardless of whether or not you hook the top bars.
The only load that will go to the wall is from when the beam deflects. It's flange (the slab) will push down on the wall and that deformation creates the load. That might be completely countered by the rotation induced by the cantilever on the opposite side of the beam. This can be determined in an FEM analysis but there is no point to doing one.
It would not be wise to rely on that slab for supporting the wall whatsoever. Just provide some extra bar/mesh in the slab in case of cracking if one really wants to.
Not sure I understand what you're getting at here.
RE: How is load transfered?
Agreed!
RE: How is load transfered?
RE: How is load transfered?
Well, since we are now discarding any cantilever action, which is definitely the easiest way to analyze the problem at hand, nothing apparently.
But in general, that's one of the first things I notice when designing cantilevers for strength. Backspan/connection may have some flexibility which is important for deflection and in this case to determine load path, but an ideal (fixed end) cantilever is just half of a simple span (inverted of course). So if I have typical simple span sizes, loads, and spans on a project, I know the same size member can cantilever half the distance for strength.
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Hokie66, yeah I understood what you meant. The OP was considering the concrete wall. I agree with you that the wall above may take some load. I would not design it as such, but considering it will be in compression (assuming the dowels act in shear) my guess is that it will provide significant strength and stiffness.
RE: How is load transfered?