Concrete wall hinge
Concrete wall hinge
(OP)
I am looking for some fresh ideas on how to approach this design.
I have a wall that spans from top of footing in the basement to the roof deck at wood truss bearing. Currently there is a hinge point at grade elevation 18' from the top of footing since there will be no floor diaphragm in this location. (see sketch) We have looked at running a monolithic concrete wall to the roof diaphragm but the roof diaphragm is nowhere close to being strong enough. We also looked at making it a retaining wall with a big footing. However I would anticipate quite a bit of movement at the time of back filling and the waterproofing would probably tear apart at the corners.
Any thoughts on how to eliminate the hinge?
I have a wall that spans from top of footing in the basement to the roof deck at wood truss bearing. Currently there is a hinge point at grade elevation 18' from the top of footing since there will be no floor diaphragm in this location. (see sketch) We have looked at running a monolithic concrete wall to the roof diaphragm but the roof diaphragm is nowhere close to being strong enough. We also looked at making it a retaining wall with a big footing. However I would anticipate quite a bit of movement at the time of back filling and the waterproofing would probably tear apart at the corners.
Any thoughts on how to eliminate the hinge?






RE: Concrete wall hinge
RE: Concrete wall hinge
Alternatively, you could use tiebacks spaced along the wall, each tied to a deadman located outside the wall.
BA
RE: Concrete wall hinge
I agree that an 18 foot high retaining wall would be monstrous and very expensive.
Another solution, although kinda crazy, would be horizontal beams spaced up the wall to distribute the lateral load to the endwalls - kinda like walers - and they could be either concrete or steel encased in concrete.. This is of course expensive to form and will not be possible if the wall is too long.
I still like the tiebacks best.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Concrete wall hinge
if that's the case then theorize a beam in the top of the concrete wall that spans that distance. make sure the header framing the opening can handle the axial load from this "beam's" reaction.
RE: Concrete wall hinge
The second page of the attachment shows the wall in plan. The opening extends 36' along the wall.
BA
RE: Concrete wall hinge
36' is a pretty long span. I like the tieback/deadman suggestion from the others. Maybe 3 of them in the middle @ 9' o.c.
RE: Concrete wall hinge
Could vertical pilasters @ say 12' o.c. on the outside of the wall? They wouldn't take up near the room of tiebacks and would stiffen the wall considerably like a counterfort wall; then the top of the wall could be designed as a beam spanning 12' between counterforts?
Just a thought.
RE: Concrete wall hinge
I do not recommend the tieback solution since these tie backs are likely to experience corrosion or be damaged by any future excavation that could take place in the future.
Good luck!