Cantilever Over Head Connection
Cantilever Over Head Connection
(OP)
I have this cantilever steel beam with overhead connection with a concrete slab - see attached sketch-. The end forces on the beam are:
M(Major) = 119 kN.M,
M(Minor) = 37 kN.M,
Shear (Major) - which will act as tension on the connection= 44 kN
Shear (Minor) = 76 kN.
My concern is how the distribution of tension on bolts would be like?, would it be OK if i treated as a base plate? or should I consider the first 2 bolts to carry the whole tension? or maybe half the bolts?
I tried to use mechanical Hilti bolts HSL-3 M24 and the ratio is OK, but I'm dealing with it as a base plate connection.
Any ideas guys? your help would be appreciated
Thanks in advance
M(Major) = 119 kN.M,
M(Minor) = 37 kN.M,
Shear (Major) - which will act as tension on the connection= 44 kN
Shear (Minor) = 76 kN.
My concern is how the distribution of tension on bolts would be like?, would it be OK if i treated as a base plate? or should I consider the first 2 bolts to carry the whole tension? or maybe half the bolts?
I tried to use mechanical Hilti bolts HSL-3 M24 and the ratio is OK, but I'm dealing with it as a base plate connection.
Any ideas guys? your help would be appreciated
Thanks in advance






RE: Cantilever Over Head Connection
How is the beam modeled in FE model?
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RE: Cantilever Over Head Connection
I would consider running an attachment plate up the concrete face to put the primary bolts in shear, not tension.
RE: Cantilever Over Head Connection
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: Cantilever Over Head Connection
That assembly looks dangerous to me with the short embedded bolts. Might think about a way to embed a full shape in the slab and weld the cantilever to that shape.
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RE: Cantilever Over Head Connection
I’d make the back span length more than 650mm if I could. Then, at the location of the first two bolts, the most highly loaded by the canti. beam reaction, I would use a squared off “U” shaped anchor rod, with the two legs pointing down and threaded, for the beam top flg., and the bent portion embedded well up in the conc. wall. This should allow these two bolts to take the entire tension and distribute it to a fair length of that wall and slab.
RE: Cantilever Over Head Connection
One leg welded to top flange and other bolted/welded to side embed plate.
Cheers! -VH
RE: Cantilever Over Head Connection
Secondly, put first row of bolts on the center of the upstand above (unless you can move the bolts so they are in shear instead), then cast in very long bolts which lap with the reinforcement (stirrups?) in this upstand to enable you to ignore the unreinforced concrete breakout mechanism, instead lapping directly with the reinforcement. This is your best bet of transferring the load into the concrete in my opinion.
Thirdly, make sure the thin concrete section can carry the load (torsion!?)
RE: Cantilever Over Head Connection