Allowable drift for a masonry chimney

[YukonOne]

I'm working on a project with one column of a moment frame embedded in a big fancy decorative/functional masonry chimney. The calculated deflection at the top of the frame/column which is about 34' tall is around 0.9". That drift seems ok to me, I'm concerned about the deflection compatibility of the frame and the chimney. Considering the chimney as a cantilever using 2L/600 as a measure seems like a place to start.

Thoughts?

 

[enginerding]

Is it possible to leave clearance between the steel and the masonry to allow independent deflections?

 

[YukonOne]

Good Question. For the purposes of this discussion I would say that the chimney is part of the structure the moment frame is supporting laterally. If there was significant independent movement we have another problem to solve.

 

[csd72]

You need to check that the chimney is not stiffer than you frame in this case, if it is then the chimney may be supporting the frame, not the other way around. This would mean a sudden brittle failure of the chimney at the design load.

If the chimney is much more flexible than the frame, then your theory on 2L/600 seems reasonable.