I am getting ready to build an earth contact home. It’s dimensions are roughly 75′ x 35′. Three of its sides will be 10″ concrete walls 8′ tall and will be below grade. The other 75′ long wall will be framed and brick (front). My question is this: Will the long 75′ concrete wall be strong enough without having any turns in it or should I put in a couple of dead men for added strength. Thanks.
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Is that 8' of backfill? I have 15' here, straight wall, engineered. The footing and footing/wall connection are the important issues. You have no need of deadmen or "turns".
Are you not required to furnish specific engineering?
Here's a standard 8' retaining wall, which is what you're building:
PAHS Designer/Builder- Bury it!
That is what I have always done for retaining walls. Seems to me that the city would require engineering for those plans.
City? Dan hasn't filled in his profile.
The wall I had engineered and built solved all my difficulties with our county inspecting dept. After the first house, they pay little attention to anything I propose. Mostly 'cause they have no idea what they're looking at. Not that they ever inspected to see if the rebar on the plan ever made it into the wall...
Lots of rebar? Looks good. They even told me I had twice the rebar necessary. Then declined to way which half. I've got 240 tons of roof over my head so I had some motivation to ensure that it stayed there. That drawing, with almost 9' wide footer, is at: http://paccs.fugadeideas.org/tom/index.shtml .PAHS Designer/Builder- Bury it!
I took a look at the website. Plan seemed quite simple enough. What did that building cost per square foot? Don't you love a challenge. Why build if all you can do is the easy stuff and just repeat the same thing over and over.
Don't you love a challenge. Why build if all you can do is the easy stuff and just repeat the same thing over and over.
Gotta have fun. But I'm not really a builder.
Not very relevant but to answer your question the shell, including floor, doors, and windows cost well under $20/ sq ft + several months of my time. Very simple plan, was to by my future furniture shop, now changed. Potential rental prices got the better of me.
More recently, I built a similar house for a client. Same 16' tall walls, windows even taller than here at 10', larger footprint with a 40' span. Came in low $20s/ft including me. Much more efficient the second time, if still very slow compared to subdivision foundation guys. On completion, that house appraised 50% higher than construction cost. We were tickled. Shell was a big part.
This is very simple construction, no reason to be anything but cheap. On the client house the crane guy and steel delivery guy were pumping me. Neither had seen anyone use so much steel residentially. When the crane guy heard how much it cost, he about fell over. Mentioned that it couldn't have been done with wood trusses as cheaply. And that 40' span steel was good for 300 tons of roof- would have been a lot cheaper without the earth load.
Commercial buildings are built similarly. There's a reason.
Here're a couple of progress pix of the first one. None of us knew what we were doing, just doing. It worked. PAHS Designer/Builder- Bury it!
You are probably already sick of hearing this, but a one hour consultation with a structural engineer would be worth every minute and every dime.
The equivalent hydraulic pressure on your wall depends upon the soil type. You can certainly take into account if your joists or trusses restrain the top of the wall or not.
In addition to concerning yourself with whether this wall will deflect across its length, you will also need to consider your moment and overturn. An engineer can sort through this for you in a matter of minutes.
If by "dead men" you mean soil tie-backs, you might save yourself some money on re-bar that way.
I don't know if you have considered ICFs but companies like Reward have some pretty good prescriptive engineering available that could save you some trouble.
What are you going to do for waterproofing?
If it were me; I would consider two pilasters (at 25 ft intervals) along back wall.
What would pilasters do for that wall?
Sorry Catskinner.
Brevity has it's problems...I could/should have said full height of wall concrete or filled block pilasters (depending on type of foundation) built into the wall. Essentially doubles the wall thickness area at said placements Usually 24 - 30 inches wide but engineers can tell you size of pilaster, and rebar# needed to build pilaster.