أنشئ حسابًا أو سجّل الدخول للانضمام إلى مجتمعك المهني.
M20-for7 days it should be67% and for28 days it should be100%...formula for cube testing: ex: m20 size of cube surface area is15*15 =225/10=22.5 for m207days20 *22.5 *67% =301.5 kn.28 days20 *22.5 =450 kn.
I agree with Eng. Jaafar.
Agree with Mr Gaafer
The question as i understand regards the gaining of the real28 gays Compressive strength using the formule of ACT for cub test, The formula is : R28 =8.09 +1.64 Ra Where. Ra. Is the result gained From the ACT Cube test, in newtons / mm2 and R28 is the predictrd28 days compresive strngth for the mix in the question. As per ( IS:), I hope i have answered the question. Abdulrahman Salihi,
Consultant Civil Engineer