ACI-305 + 306 + 308 vs Contractor

[boffintech]

Atlanta, GA

In the SE US we are now supposed to be taking the IBC and the Schedule of Special Inspections seriously and the Special Inspector is now required to “periodically” inspect for the "maintenance of specified curing temperature and techniques".

This gives rise to the following:

Concrete for columns, shearwalls, and other vertical elements is poured on one day and the formwork is stripped the following day.

True or False:

Except for protection from freezing on the night immediately following concrete placement, vertical concrete elements are exempt from any and all of the concrete curing requirements found in ACI 318, 305, 306, and 308.

 

[henri2]

False.

We discussed this issue last year.

http://www.eng-tips.com/viewthread.cfm?qid=147680&page=4

What is being done about enforcement of special inspection code provisions in your neck of the woods...is it improving?

 

[DonPhillips]

Hit or miss in Ohio. I get a lot of blank stares from Architects when I do a plan review and ask for a statement of special inspections. I typically get a call asking me what I am looking for. The SER is not sure how far to go either.

Part of the problem, I think, is each jurisdiction probably has a different comfort level on what a field inspector can inspect, or how much information has been asked for in the past. After a footing inspection, I am sure few asks for test reports on the concrete. Similarly, I doubt anyone is asking for the grout cube test reports for masonry construction. For simple buildings, this is probably not a real concern, and for substantial projects, decent special inspections will be part of the project.

My experience in western states was positive since the UBC has had a lot of special inspection language in it.

Don Phillips

http://worthingtonengineering.com

 

[boffintech]

What is being done about enforcement of "special inspection code provisions in your neck of the woods"?

Well I'm not at the upper levels of project management so I don't know what happens after all the various reports are turned in.

Recently I have heard of some projects that could not get a CO because they failed to get inspections. They had to go back and get some one to bite off on their work. It won't be me. Last winter/summer I inspected all the rebar/PT and concrete on a 4 story office building. During construction the masonry started. I remember walking past the masonry work as it was going up and thinking what an absolute disaster it was. I made notes in my field book on 5 separate dates where I told my PM that they were lucky I wasn't doing the masonry inspections or they would have to "start over". Three months after the concrete topped out I was called back to the job only to learn that I had been lined up to perform all the SI for COMPLETED masonry work. I asked the contractor, "You guys have 10 guys with chipping hammers?" The contractor just stood their in disbelief. So we walked the job to look at the work and I gave an hour long dissertation on Part 3-Execution of ACI-530. That was the last I heard about it.

 

[boffintech]

OK, back to the question of curing vertical concrete members. The code requires it. Clearly IBC-06, ACI-318, and ACI-308 require that ALL concrete elements be cured.

The contractor now claims that leaving the column forms in place for 1 to 3 days is all the curing that is required because the mix has been coming up to 70% at 7 days. (Not field cured strength test specimens mind you, just the regular lab cured cylinders.)

I'm reading 308 and I just do not understand what this guy is talking about. What am I missing?