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Single Seismic Resisting Column

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IAmNotVerySmart

Structural
Dec 11, 2019
14
The project is a remodel of a existing home. A wall is being demoed and to replace it a single column and beam are being placed. The attached image is the proposed design for the system. I imagine something like this is possible if the proper straps are connected to the beams and the column is designed as a cantilevered moment resisting column. I have been thinking that since there is a moment on each side then do both moments cancel one another out? Or is it instead that there is double the amount of force on the columns foundation.
 
 https://files.engineering.com/getfile.aspx?folder=9f9c32ab-20c0-4286-a3e4-8f29bae37bbd&file=Structural.pdf
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This doesn’t sound like a very smart idea. The cantilever is a poor mechanism.
 
i would rather apply moments to the columns due to pattern loading.
secondly, i would listen to @ThorenO2.
 
I have used cantilever columns many times for residential but they have limited capacity and a rather low response modification factor so there are not many places where their use is feasible. I mostly use them for porch or patio covers that cantilever fairly far from the main diaphragm. I have never used them as part of the main LFRS of the structure.
 
If it is resisting seismic loading, how do the moments cancel out, even if you can develop the fixity at the bottom to achieve cantilever action?
 
I have yet to get a cantilever wood column to work. That system isn't even recognized in the ASCE. Closest you can get is "Timber Frame". Plus as the mentioned above, it's tough to get fixity at the base. Simpson StrongTie has a connection for it but you can't use those connections in SDC D-E plus the capacity is really limited.
 
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