Abstract
In this research, the effects of some parameters on the heat of hydration for two concrete mixes have been studied. The mixes are with and without 15% micro silica as a cement weight replacement designated (M2) and (M1) respectively, and Three concrete mixes by weight namely, (1:2:4 , 1:1.5:3 , and 1:1:2) at uniform consistency that is a constant slump of (75-100 mm) for both(M1) and (M2), and Two curing methods, moist and air cured, While the internal temperature for the specimens was measured for (28) days : at the 1st two days at intervals of half an hour then at intervals of (3 hrs) for the 3rd and 4th day, while at intervals of (6 hrs) until (28) days. The results of the research proved that the heat of hydration was higher at the 1st day than that at the 2nd day, fluctuating during the 1st (48 hrs) . The fluctuation reduces gradually to a steady rate at later ages, While the heat of hydration for all mixes and at all ages (except the 1st day) was higher for air cured specimens than that moist cured for same condition, As the cement content increased the heat of hydration (for mixes M1) increased accordingly and also the addition of silica lowered the internal concrete temperature for M1 mixes (at high and moderate cement contents) in opposite of few cement contents.
