Thermal activation of ordinary Portland cement-slag mortars

摘要

Thirty one mix proportions of ordinary Portland cement (OPC)-slag mortars (OSM) used to study the effects of temperature on early and ultimate strengths. Three levels of slag (0%, 40%, and 50%) and different temperatures were used; it was found that 50% is the optimum level and 60 ℃ with 20 h duration is also optimum. The maximum strengths obtained of optimum mortar, at 3 and 7 days, for specimens cured in the air, are 55.00 and 62.00 MPa, respectively. These strength levels are 64.50% and 66.50% greater than those without heating. The results show for 0 and 2 h heating time, the strength of specimens cured in the water are greater than those cured in the air, but for 4-26 h, this statement is reversed. This is a novelty, is very important in the precast industry and has many advantages for arid regions to overcome curing of concrete structures.