hi everyone, What could possibly caused the 7-day strength of mortar to fail and be able to pass in the 3 & 28-day strength requirement?
Ted Krapkat
Hello Norew,
This sounds like a testing issue. Has this been observed on just one test sample, or is it happening consistently?
Regards,
Ted.
norew
This has happened already for quite a number of samples.
Ted Krapkat
Hello Norew,
Is the cement in question GPC or PPC?
By how much is the 7d strength failing? If it is only failing by a small amount then it may be that there has been a change in the distribution of cement particles somewhere in the range 3-32um, or a change in the amount of C3A in the clinker or the ratio of C2S to C3S.
Or even possibly a change in the alkali sulphate level in the clinker. (the quantity of soluble alkalis affects clinker mineral reactivity and hydration rate)
Regards,
Ted.