Cube samples taken and tested for this pour
Why — act while you have leverage
The cube test is the only evidence of what strength you actually received. Without it, a weak pour is a matter of opinion, and the opinion that counts will be the contractor's.
What to look at
- Cubes cast in your presence, from the same concrete
- Date and pour location marked on each cube
- A lab report naming the mix and the 28-day result
- 7-day cube test report
- 28-day cube test report
Documents to ask for
- 7-day cube test report
- 28-day cube test report
How to check it yourself
Cubes are cast at the pour from the concrete going into the structure — not from a separately mixed batch — marked with the date and location, cured in water, and tested at 7 and 28 days by a lab. The 28-day report is the one that matters and belongs in your file.
Where this comes from: IS 456:2000 cl. 15 (acceptance criteria) and cl. 16; IS 516 (method of test) (indian standard or building code)