My project has fieldstone basement walls, circa 1840, good condition. dirt floor. 6 foot overhead. i want more. Rented conveyor. excavated 1 foot in 2 stages. Formed, rebarred and poured 2 foot high pony wall, 4 inch cross section, to deal with lateral forces at bottom of and below fieldstone wall. a higher wall, bigger crosssection, will be poured over this wall to buttress fieldstone wall. rebar was extended out of ponywall to tie in rebar of the later pour. i will also rebar and pour a slab floor. my question: If a footing and a short wall can poured together, can a floor slab and a short wall be poured together?
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The short answer is "yes".
You lost me on the detail. Can you post a drawing? Reinforced concrete retaining walls need substantial footings. You're using the floor as the footing? If so, the reinforcement between the wall and floor is critical and will consist of more than simple L-shaped rebar.
PAHS Designer/Builder- Bury it!
I'll post a drawing. I expect I'll need a soil guy (and maybe an engineer for load details?) before the actual substrata,slab/wall dimensions, rebar pattern, etc. can be determined but a basic concept drawing will help this discussion. Standby for that. Thanks for pitching in. There's some experience and depth at this site. I want to keep this thread going.,
You're welcome. There're guys here with considerably more experience than mine, but you will need to find your own engineering. Here's a page from a standard retaining wall book, which actually does employ only L shapes. The engineer I use is fond of ____/ set with the long side at 45º to the wall and footing, coupled with some hefty L's. Typically, I'm good for 15' of dirt against the wall, requiring considerably more wall and footing than the attached drawing.
I have something coming up, not a retaining wall, that will require a soils guy. First time I've ever used one. Didn't know until I started hanging out here at BT that it was a good idea. Almost never used around here in Va- and usually the walls don't fall down. <G> Our building dept doesn't have a clue about reinforced concrete so they leave me alone. PAHS Designer/Builder- Bury it!
Got it. Thanks. My sketch (attached) is a cross section detail for concept only, with dimensions not to scale.<!----><!---->
Viewed with the existing fieldstone foundation on the right margin, the short wall ,which I rebarred and poured to contain lateral forces after excavating, is the small rectangular element on bottom right. The "L" shaped element is the proposed slab and final wall. The sketch , hopefully, will help the viewer visualize the two questions I have: (1) Can the slab/wall "L" be poured as a single structure-no joints?; and (2) If a monolithic pour is possible, how high can the wall be poured? The concrete in the slab must be sufficiently set up to resist the force of gravity on the column of liquid concrete in the wall form. I'm getting into the Black Arts here with the timing and execution of the actual pour. The existing foundation, vintage 1837, is in pretty fair shape. This is not a retaining wall, per se, and the weight of the building will not rest upon it. My incentive is a dry basement and my building inspector. There is a seasonal wet/dry cycle right now and I want to eliminate that. Basements are swimming pools in reverse. My current "swimming pool" leaks. My building inspecter - very saavy, experienced- will want to see some specific plans. If it's possible to monopour this thing I want the engineering, design and the procedure to be all on paper. Thanks for the attachment. I'm looking around. Picking up info.
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A) You're kinda new here, welcome. Also kinda nice if you'd fill in your personal profile, found by clicking on novaterra. Particularly useful for regional differences. Irfanview http://www.irfanview.com/ is a free easy-to-use program that manages jpg size nicely. Those of us out in the sticks on dailup get huffy about overly large files. Nice guy that I'm not always, I resized it. Also much easier to view now.
B) This is what I thought you were originally talking about. What I don't know is how strong it needs to be, but that's really a matter for an engineer.
C) I'm soon to pour my first monolithic wall/footing of 4' wall height. Needs to be a stiff mix, which I normally do, but is very unusual in our area. I like a 3-4" slump. So does my engineer. How high would you like?
D) I assumed you didn't have a building to support, but soil to resist, making it a retaining wall. Short ones are not much of a challenge.
E) Concrete is pretty water tight, but it cracks. That's where exterior water-proofing, not damp-proofing, is commonly used. Difficult at best for your application.
F) If you view it as "Black Arts", might be best to hire somebody with experience for the pour. You're also likely to get a much flatter floor.
G) Good luck.PAHS Designer/Builder- Bury it!