low core breaks 2

[kenby]

I recently had 2.87" core samples taken from a footing. We poured a 3000 p.s.i. mix. Our breaks showed an average of 2920 p.s.i. Would this be a passing test result according to ACI?

 

[BigH]

The normal standard on core to "pass" is that you take three cores and the average of the three shall be greater than 85% of the specified strength and no single core is be less than 75%. I do not have the ACI code but the above is from the Canadian code and is similar to that in India and many other places.

 

[techmaximus]

ACI-318 - 5.6.5.4 — Concrete in an area represented by core tests shall be considered structurally adequate if the average of three cores is equal to at least 85 percent of fc and if no single core is less than 75 percent of fc. Additional testing of cores extracted from locations represented by erratic core strength results shall be permitted.



Techmaximus

 

[kenby]

Thank you both for the info.