Minimum concrete cover (ACI 318)

[TimNY]

Does anybody know what ACI specifies as the minimum concrete cover for #5 (plain steel, not coated) in a footing?

The footings are not exposed to the weather.

Thanks (guess I should invest in ACI 318)

Tim

 

[Mark K]

If it is cast against the earth 3". If formed but exposed to the earth or exposed to the weather 1.5" for #5 but 2" for #6 or larger.

 

[KZQuixote]

Hi Tim,

I've got ACI318-08.

Page 91 speaks to Cast in place concrete (nonprestressed)

(a) Concrete cast against and permanently exposed to earth 3 in. There is no break down for bar sizes till you get away from cast against earth.

Hope this helps.

Bill

 

[TimNY]

Thanks Mark and Bill. I should probably order 318 but at $135.. ouch!

So I think I was correct in saying they can't use the bar to keep the forms in place? 16" wide footing, 16" wide bars.. not sure why they had them in there (not on the plans) but told them to remove or cut 3" shorter.

They had the same problem with the bars parallel with the footing as well.

I knew it was wrong.. Thought it was in the IRC but the only thing I found was anchor bolt distance from edge in a monolithic pour.

Thanks again for the expeditious help!

Tim

 

[pyrguy]

Do a search, I did not bookmark the page but ACI318-05 is available as a PDF download for free.

 

[Daddy-0-]

Similar question. What is the required minimum edge clearance on anchor bolts set in a poured concrete wall? Don't mean to hijack the thread just curious if that is IRC or ACI or what. Thanks.

 

[Phil]

In ACI 318-05, cast-in place anchors that are not torqued have the same cover requirements as reinforcing. However, the capacity of an anchor will be limited with small edge distances.

 

[Mark K]

Strictly speaking it could be argued that if the steel is not for reinforcement or arguably steel anchors addressed in appendix D that ACI 318 does not provide guidance for concrete cover on steel in concrete.

 

[Phil]

Mark K

See ACI 318-05 section D8.2.

D.8.2 — Unless determined in accordance with D.8.4,

minimum edge distances for cast-in headed anchors

that will not be torqued shall be based on minimum

cover requirements for reinforcement in 7.7. For castin

headed anchors that will be torqued, the minimum

edge distances shall be 6do.

D.8.4 — For anchors where installation does not produce

a splitting force and that will remain untorqued, if

the edge distance or spacing is less than those specified

in D.8.1 to D.8.3, calculations shall be performed

by substituting for do a smaller value do′ that meets

the requirements of D.8.1 to D.8.3. Calculated forces

applied to the anchor shall be limited to the values corresponding

to an anchor having a diameter of do′ .

 

[Daddy-0-]

How about this? LOL

View attachment 453

View attachment 453

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[peach]

that doesn't work, Daddy... sorry. The bolts need some meat in the plate or the first windstorm/earthquake is going to pull the plate off the anchors.

 

[RJJ]

Daddy o I guess they need an engineer for that one or contact Hilti!

 

[Daddy-0-]

The engineer had them replace 64 bolts with new epoxied threaded rod. This contractor does that 5 out of 10 times. They have an engineer on retainer. Language barrier with the subs mixed in with a lot of I don't care as long as it closes on time. Every area has a contractor or two like this but unfortunately this one is national.

 

[Mark K]

It was stated "Daddy o I guess they need an engineer for that one or contact Hilti!"

I will suggest that if an engineer is needed a manufacturers rep cannot be substituted.

 

[Daddy-0-]

Yes. Mark. I agree.

Hilti tells them how to install it.

The engineer tells them where, what, how deep, and how to install it and then watches them do it and then gives me a report saying "structurally adequate for intended use." Yes again. Engineer required.