bolting thru concrete
bolting thru concrete
(OP)
I am reinforcing an existing concrete beam in a foundation wall by attaching a C15X33.9 to each side, basically clamping it. I want to develop the end reactions by thru bolting. My question is, does anyone have a procedure for checking the concrete for the bolt loads?
I have checked with Hilti, and they say they don't recommend that there adhesive anchors be used in a thru bolting application. Would a shear friction appraoch be acceptable? If you rely on bearing on the concrete, what would the dstribution of bearing stress look like?
I have checked with Hilti, and they say they don't recommend that there adhesive anchors be used in a thru bolting application. Would a shear friction appraoch be acceptable? If you rely on bearing on the concrete, what would the dstribution of bearing stress look like?






RE: bolting thru concrete
Sketch your connection. Label the loads and reactions properly. Perhaps the rep can't see clearly how your connection conforms to their criteria, or perhaps they may suggest how to design the connections so they do conform.
We need more information on your connection to evaluate it.
RE: bolting thru concrete
You could also install short C below the C15 as a "column". The column could be fastened to the wall with epoxy anchors to transfer the load to the existing wall.
RE: bolting thru concrete
RE: bolting thru concrete
Can you field weld a 3/8" plate to the flanges of the channels so as to create a boxed section around the concrete at the same locations that you would place the bolts? I'm not saying box in the entire column, but just boxing the areas for about 8" sections at each location of the would be bolts.
RE: bolting thru concrete
RE: bolting thru concrete
RE: bolting thru concrete
I have done it in a simialr manner several times. I have thought of and tried to "refine" the methodolgy several times. Unfortunately, each time i think I have an alternate way something comes along to bring me back to the way you described.
weron4u,
I haver added the plate in a few instances.....sort of belts and suspenders.....
RE: bolting thru concrete
Are you reinforcing a beam on a foundation wall or a 12" thick concrete wall at an opening?
If it is wall like a deep beam, the channels attached may not be rigid enough to help transfer load from wall. They may just work like a horizontal tie to form the truss mechanism.
Even if it is only a concrete beam, you need to check the stiffness to see how much help the channel can provide. I mean if the channel stiffness is much less than the concrete beam, you need quite a deflection to get the load transfer, the deflection may not be accepted.
RE: bolting thru concrete