column bracing
column bracing
(OP)
I have a multi storey stair tower running parallel to the exterior column line. Due to the location of the tower I can only brace the exterior column with the intermediate stair landing. Has anybody encountered this situation, btw the building is steel construction.






RE: column bracing
I would design the column as unbraced for its full height.
DaveAtkins
RE: column bracing
Why not? Your bracing only needs to carry something like 2% of the axial load. With a properly detailed brace and proper load path to the LFRS, this would greatly reduce your column size. We have a responsibility toward our clients to provide safe AND efficient designs.
RE: column bracing
DaveAtkins
RE: column bracing
I depended upon moent connections at all the horizontal beam-to-column connections.
RE: column bracing
Thanks
RE: column bracing
The exterior beam from the left would help brace the column in weak axis bending - cantilevering off the diaphragm and framing just to the left of the stair shaft.
RE: column bracing
I did state "properly detailed" in mi response. Just follow your load back to the LFRS. If your stair landings are not connected in any way to the LFRS, then obviously you cannot. But if the landing is supported, say, at a shearwall, then it's fairly simple.
RE: column bracing
Yes I was counting the bracing about the weak axis but how do you brace about the strong axis? If the intermediate landing was directly connected to the column using a beam and hung from the floor on the inside of the landing and design the hanger as a cantilever taking the brace force?
RE: column bracing
Is the left end landing an intermediate platform between 2 stories, or level with the floors? If it is the latter, is there an edge beam at S end of the opening to intercept the interupted floor beams? Is this a steel stairway?
RE: column bracing
If you have a landing at the main floor level, with a stair beam from the column to the main floor on the inside, that would also brace the column.
But the edge beam also participates - might have to check against strength and stiffness of it as a brace, but it might work.
RE: column bracing
KSLEE In my situation the intermediate landing would be located near gridline FG with the landing beam supported at column FG on one side and using hangers from the floor edge beams above to support the rest of landing. Yes this building is steel construction.
Thanks for taking time to provide feedback
RE: column bracing
RE: column bracing
RE: column bracing
RE: column bracing