Thoughts on multistory X bracing with zipper column
Thoughts on multistory X bracing with zipper column
(OP)
Hello everyone,
What are your thoughts on multistory X bracing with zipper columns (attached) for seismic design?
I ask this because in textbooks and references I haven't seen this type of bracing, though for me it behaves the same as the inverted V bracing with zipper columns.
I know Bruneau's book has some pros and cons for each type of bracing but this one in particular is not there. So I was also wondering if you know references for this type of bracing.
Best regards.
What are your thoughts on multistory X bracing with zipper columns (attached) for seismic design?
I ask this because in textbooks and references I haven't seen this type of bracing, though for me it behaves the same as the inverted V bracing with zipper columns.
I know Bruneau's book has some pros and cons for each type of bracing but this one in particular is not there. So I was also wondering if you know references for this type of bracing.
Best regards.






RE: Thoughts on multistory X bracing with zipper column
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: Thoughts on multistory X bracing with zipper column
At the beginning I put that zipper column to distribute the weight at 3 points instead of 2, but I'm not sure if it will have detrimental effects over the lower braces, apart from the obvious additional axial force.
RE: Thoughts on multistory X bracing with zipper column
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: Thoughts on multistory X bracing with zipper column
The beam should be designed for the full gravity load (spanning main column to main column) and the additional load generated from a buckled brace and one in tension. Also the axial load in the beam if present.
If you add the zipper column, you need to determine how much gravity load gets distributed to each beam and design both accordingly along with what I stated above.
RE: Thoughts on multistory X bracing with zipper column
Just my 0.02$, this is certainly an interesting discussion.
RE: Thoughts on multistory X bracing with zipper column
RE: Thoughts on multistory X bracing with zipper column
My only concern was that mentioned by DETstru, but my analyses so far tell me that if one lower brace buckles, the upper truss resists the loads from the dead and the tension brace.
Another concern is that I haven't seen this type of typology in similar structures, and I was simply wondering why.
(MonsieurR)
RE: Thoughts on multistory X bracing with zipper column
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.