x-bracing intersection connection
x-bracing intersection connection
(OP)
hi
we have been using x bracing in our support structure,
refer the attached sketch
where the support structure was designed as SCBF(special concentric braced frames)
since there is no length at x-bracing intersection for making gusset conn, we have
made direct pipe to pipe welding at intersection.
The pipe to pipe connection has been designed as per sec.K of AISC 360-10 for
the actual tension/compression brace force coming from staad analysis.
But the client asking to consider higher forces (1.6fy.Ag) as per aisc 341-05 for designing this conn.
we have already designed corner gusset connection as per aisc 341-05 for higher forces 1.6.fy.ag.
since there is no gusset / reduction in gross area I think we can design the intersection only for actual
staad analysis forces.
please clarify.
thanks
SENTHILKUMAR.B
we have been using x bracing in our support structure,
refer the attached sketch
where the support structure was designed as SCBF(special concentric braced frames)
since there is no length at x-bracing intersection for making gusset conn, we have
made direct pipe to pipe welding at intersection.
The pipe to pipe connection has been designed as per sec.K of AISC 360-10 for
the actual tension/compression brace force coming from staad analysis.
But the client asking to consider higher forces (1.6fy.Ag) as per aisc 341-05 for designing this conn.
we have already designed corner gusset connection as per aisc 341-05 for higher forces 1.6.fy.ag.
since there is no gusset / reduction in gross area I think we can design the intersection only for actual
staad analysis forces.
please clarify.
thanks
SENTHILKUMAR.B






RE: x-bracing intersection 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: x-bracing intersection connection
And in answer to your question - In my view you do need to use the amplified load on all brace connections, whether they occur at the ends or at the intersections.
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RE: x-bracing intersection connection
Also you can design two story "X" brace to avoid the connection of the two pipes.
RE: x-bracing intersection connection
I agree with the others however that the proposed connection likely won't be capable of transferring even the analyzed bracing force, much less the amplified force. Why can't you just introduce a gusset?
RE: x-bracing intersection connection
RE: x-bracing intersection connection
I understand we do not have a complete set of drawings but, it appears that you have a slotted pipe with no cover plate, the material removed is required to be replaced. Additionally its not clear where the yield line, 2t, mechanism is located. If you are trying to have the plate in-plane buckling of the plate, there are limitation on the distance from the edge of the plate to the end of the pipe also the plate is typical perpendicular to the gusset plate.
RE: x-bracing intersection connection
RE: x-bracing intersection connection
thanks for your replies,
this x-bracing is already in site, we want use with minimum repair,
what would be the good solution?
introducing the gusset at center, but the there is no enough length
RE: x-bracing intersection connection