Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
(OP)
Hi All,
I have an interior braced bay condition where I need to design the foundations for the bracing reactions. In particular I am focused on the horizontal reaction from the bracing. In the past I would have designed the footings for the moment; however, I am trying to take a fresh look at this situation. The piers are going to be surrounded by a concrete slab. Is it reasonable to argue that the slab is going to restrain the top of the pier and only design the footings for the vertical components? Assuming the slab checks out for bearing, etc. What about the isolation joint between the pier and the slab? Look forward to hearing how you guys handle this situation.
Along that same line I also examining how I am handling the braced bay forces in the sidewalls. Normally I use poured concrete foundation wall tied into the piers and the footings and that can easily handle the strut load between the columns. In this case the owner insists on block foundation walls. I would imagine that I would need to fully grout the cores between the two columns and add vertical and horizontal reinforcing. What I am unsure of is the best way to tie into the poured piers. Again I would appreciate any thoughts or suggestions.
Thank you
I have an interior braced bay condition where I need to design the foundations for the bracing reactions. In particular I am focused on the horizontal reaction from the bracing. In the past I would have designed the footings for the moment; however, I am trying to take a fresh look at this situation. The piers are going to be surrounded by a concrete slab. Is it reasonable to argue that the slab is going to restrain the top of the pier and only design the footings for the vertical components? Assuming the slab checks out for bearing, etc. What about the isolation joint between the pier and the slab? Look forward to hearing how you guys handle this situation.
Along that same line I also examining how I am handling the braced bay forces in the sidewalls. Normally I use poured concrete foundation wall tied into the piers and the footings and that can easily handle the strut load between the columns. In this case the owner insists on block foundation walls. I would imagine that I would need to fully grout the cores between the two columns and add vertical and horizontal reinforcing. What I am unsure of is the best way to tie into the poured piers. Again I would appreciate any thoughts or suggestions.
Thank you






RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
google foundations for metal buildings, they have different approach how to resist lateral loads (tie rods, etc..)
RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
At the the masonry infill wall, my first choice would be to not use it at all. If you must use it, I imagine that you'll need to have dowels drilled and epoxied into the vertical faces of the piers that lap with your CMU horizontal reinforcing.
I think that Delagina was referring to this book: Link. If so, I second the recommendation as I have it as well. Even though I don't agree with everything, it's great to see what assumptions are common in the industry.
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
KootK, am I to take it that you design all your braced bay footings for overturning and don't rely on the strip footing or the grade wall?
RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
Linking in a "non-structural" floor slab which usually is separated by an expansion joint doesn't sound right to me - especially if you are dealing with a larger building.
Yes - OK for PEMB but not for more significant structures.
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RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
RE: Resisting Longitudinal Braced Bay Reactions with Slab and Grade Beams
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.