in the past. Many houses and garages were built for years without any
reinforcing and are still standing--at least in less shakey places. Our
building code (Part 9-Small Buildings and Houses) will allow plain
concrete basement walls up to 8 ft. Occasionally, a customer needs to
have something engineered which the municipality can demand. I always
tell my customers that calcs for a 8 ft high basement wall will indicate
it needs reinforcing despite the code. Even for those walls within the
code, I still throw in a horizontal bar in the top.
Gary
Jordan Truesdell, PE wrote:
> I believe a #4 at the top and bottom are required, though I can't
> remember the paragraph. IBC prescriptive foundation walls violate
> practically all of the spacing and minimum steel provisions of ACI318,
> and current top-of-wall connections between foundation walls and the
> diaphragm violate load path physics (up through 2003).
>
> You will find that additional reinforcing may be required based on the
> seismic design category, and no mention of such reinforcing is made in
> the vicinity of the prescriptive design tables (I know that's the case
> in the IRC; not certain in the IBC).
>
> Settlement and shrinkage cracks generally don't become critical within
> the 1/5 year warranty required by my state, so builders don't give a
> rats @ss about the steel, and temperature steel in foundations that
> are constantly held between 55F and 70F isn't really necessary (at
> least, I presume that's the logic for omitting it by the IBC). It's
> either that or the prescriptive walls tend to be in buildings small
> enough that only a few people will die in the event of a failure, so
> that's okay in the eyes of the ICC (and their builder-lobby members).
> *shrug*
> Jordan
>
>
>
> Jim Wilson wrote:
>> The IBC provides prescriptive design tables that allow some concrete
>> foundations to have little or no vertical reinforcing. The code
>> appears to be absent on horizontal reinforcing, yet that is often the
>> first failure mode due to settlement and/or wall shrinkage. Is there
>> a minimum horizontal reinforcing requirement requried by the IBC that
>> I am missing? This is not a crack critical wall. And this NOT an
>> engineered wall - I am only looking for code interpretation and good
>> practice info.
>>
>> If there needs to be horizontal reinforcing, vertical steel would be
>> required to support the horizontal bars. What is an appropriate
>> spacing for this purpose? 8ft?
>>
>> Jim Wilson, PE
>> Stroudsburg, PA
>>
>>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> * Read list FAQ at: http://www.seaint.org/list_FAQ.asp
> * * This email was sent to you via Structural Engineers *
> Association of Southern California (SEAOSC) server. To * subscribe
> (no fee) or UnSubscribe, please go to:
> *
> *
http://www.seaint.org/sealist1.asp
> *
> * Questions to seaint-ad@seaint.org. Remember, any email you *
> send to the list is public domain and may be re-posted * without
> your permission. Make sure you visit our web * site at:
> http://www.seaint.org ******* ****** ****** ****** ******* ******
> ****** ********
******* ****** ******* ******** ******* ******* ******* ***
* Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
* This email was sent to you via Structural Engineers
* Association of Southern California (SEAOSC) server. To
* subscribe (no fee) or UnSubscribe, please go to:
*
*
http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad@seaint.org. Remember, any email you
* send to the list is public domain and may be re-posted
* without your permission. Make sure you visit our web
* site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********