Concrete Poured after 90 minute limit
Concrete Poured after 90 minute limit
(OP)
Concrete was poured at a shear wall at about 110 minutes. According to ASTM C-94, "The discharge of the concrete shall be completed within 1 ½ hours after the introduction of the mixing water to the cement and aggregates, or the introduction of the cement to the aggregates." Any thoguhts on how to proceed now that the pour has already happened? One thought I had was to request that core samples be taken and tested. The did not take cylinders of the concrete that was 110 minutes old.






RE: Concrete Poured after 90 minute limit
RE: Concrete Poured after 90 minute limit
Is it a super critical wall where the building would fail if it failed in shear, or are there others that were not poured at the same time im line with it that could pick up the load if it failed?
I would at least look at the answer to these questions, and perhaps some others, before you fire your loaded gun. :)
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Concrete Poured after 90 minute limit
A 20-minute breach of the 90-minute criteria might not be an issue depending on environmental conditions and the mix design. Keep in mind that ASTM C94 has had the 90-minute criteria in it for many years, mostly based on a basic mix design with cement, aggregates and water. Admixtures can change this criterion.
There is no reason to remove good concrete. Evaluate the concrete. If good, leave in place...if not good remove.
RE: Concrete Poured after 90 minute limit
Dik
RE: Concrete Poured after 90 minute limit
RE: Concrete Poured after 90 minute limit
the whole point of the 90 min. limit is to make sure the concrete doesn't set up during the placement. if you dont have cold joints in your concrete you may be able to convince yourself that you're ok, but it's going to require the contractor to do some destructive and maybe non-destructve testing on their own dime.
RE: Concrete Poured after 90 minute limit
It is not difficult or costly to check the temperature of the delivered concrete to determine weather effects on setting time. - Curing is a different story.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: Concrete Poured after 90 minute limit
RE: Concrete Poured after 90 minute limit
I second the idea of doing some in place testing and going from there.
PE, SE
Eastern United States
"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi
RE: Concrete Poured after 90 minute limit
AITA