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Vertical cracks @ grout locations cmu basement wall

Vertical cracks @ grout locations cmu basement wall

Vertical cracks @ grout locations cmu basement wall

(OP)
This residential basement wall is showing vertical cracks, full height, in nearly every filled core.  I am under the belief that the grout froze and expanded before it cured.  I'm in upstate NY and this was done around 2 weeks ago, so freezing temps is highly likely.  

8" wall, reinforced at 48" oc, about 9ft tall.  It has been backfilled since. The crack goes clear from one side through the other, even through the waterproofing parging.

Has anyone seen anything like this before?  I'm not too worried about the vertical cracks in the blocks, I am worried that the grout core and rebar bond has been compromised.  Thanks in advance for your opinions.

RE: Vertical cracks @ grout locations cmu basement wall

You may have to have a core sample taken and tested. Never had the grout freeze up on me. It would also be likely the mortar may be a problem also.

RE: Vertical cracks @ grout locations cmu basement wall

Having never dealt with masonry under cold weather conditions I do have some questions.

Questions for jfudo :

1. From available weather records what were the approximate mean and minimum daily temperatures when the wall was built? Were they below 40 deg F?

2. Does the construction of masonry walls of R-3 residential occupanices in the jurisdiction the project was have to meet MSJC Spec cold weather requirements?

3. If the response to the previous question is in the affirmative, were the rules adhered to (i.e was there any inspection at the time of construction)?

4. Is there any possibility of the wall bending horizontally out of plane between supports? I ask this because of the vertical through cracks

Question for forumites:

5. What destructive and or non-destructive testing are normally carried out to evaluate the structural condition of a wall that has experienced this type of distress..are infrared techniques commonly used?

RE: Vertical cracks @ grout locations cmu basement wall

(OP)
Thanks for the responses, my answers:

1.  It was above freezing during the day, probably right around 40, and was mid 20's at night.  I am guessing, as I wasn't involved with this project until this point.  The contractor's memory is a bit, how do you say..."hazy"

2. We only have state code, which is the IBC residential code, which references ACI 530.  There is of course cold weather specs in there.  

3. The one thing I'm confident of, is that there were no steps to protect the construction from cold weather.  

4. From the looks of it, and by the spacing of the cracks, I don't think it was horizontal bending.  The cracks aren't spaced in a way to demonstrate this, and there are a couple places where the cracks are in short (3ft) lengths of wall that wouldn't be under enough bending stress horizontally.  

RE: Vertical cracks @ grout locations cmu basement wall

My guess would be that contractor added a little water at the site before placing grout. It froze. I'd tell contractor to dig up the wall tear it out and do it right. Be onsite for removal and reconstruction.

Richard A. Cornelius, P.E.
WWW.amlinereast.com

RE: Vertical cracks @ grout locations cmu basement wall

If the cracking occured before backfilling took place, then it is very possible the destructive effects of cold weather is the primary causative factor...as you had suspected.

That cold weather can reduce compressive strength, durability, adhesion bond, reinforcing bond (your main concern) etc seems pretty well documented.

IMO, an evaluation should entail a visual examination backed up by tests (NDE, simulated tests to measure effect of cold weather on reinforcing bond, etc). Without this information, you risk making a judgement call which may be diametrically opposed to reality.

Apart from the costs of the evaluation, there are costs involved in repairs...these costs can add up.

At the end of the day, you may decide to do what Richard Conrlius suggests...i.e "tell contractor to dig up the wall tear it out and do it right. Be onsite for removal and reconstruction. "





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