"Walking" column system

[formi]

Hello and welcome!

Has anybody ever used "walking" column system? Do you guys have any literature/references how to deal with it? (i mean - design procedures or sth like that).

 

[TLHS]

I've never done this before, but it looks pretty straightforward. The floor at the top of the widened column acts as a tension chord and the one at the bottom goes into compression. You have to design the column to hold the vertical force plus the shear and moment necessary to make the rest of the system work. So it's just beam-column design after you draw out your force diagram.

I'd want to draw a couple of scenarios to make sure I know what happens when there's unbalanced loading, though. I'm guessing it would depend on what your lateral force system looks like. You should just be able to dump the extra diaphram force into the building core or wherever most of your lateral force goes.

 

[hokie66]

TLHS has the idea. I have never heard the terminology "walking columns", but offsetting columns by this method is common. The column force travels diagonally through the widened transfer column, so the horizontal component of the force has to be resisted by the floors.

 

[KootK]

I like strut and tie for the "wallumn" portion. Be se sure to consider strain as well as strength at the tie-back diaphragms. If you're in seismic country, beware: in the absence of symmetry, this scenario creates a permanent lateral demand on the core and potential for seismic ratcheting. Keep an eye on diaphragm connection at the tie-back floors.

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