What Causes This Type of Crack?

[swearingen]

The enclosed pictures show the lower edge of a pile-supported slab. Along part of the edge, the lower corner is showing a horizontal crack. What might cause this type of cracking? Corner reinforcement too close to the corner? Wet soil providing too much of a temperature gradient for the concrete as it cures?

Would love to hear the expert's thoughts...

Thanks!

-5^2 = -25 ;-)

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[hokie66]

I'll go with too early form removal. There are some black dots, likely holes, below the crack. Likely some projections like nail heads, inside the form.

 

[LittleInch]

Did the formwork move slightly after final filling when the concrete was curing, but still green?

Is there a bulge in the footing or is that an optical / camera error. What does it look like in line?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[1503-44]

What is the extent of the cracks going into the cap? Have you broken out a damaged bit to find out if it is limited to the corner alone? Is this only occurring in the wet soil?


--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."