Additives are chemical compounds that are added to concrete during its manufacture to modify one or more of its properties. The first additive used in modern concrete was the accelerator, intended to shorten the time ...Additives are chemical compounds that are added to concrete during its manufacture to modify one or more of its properties. The first additive used in modern concrete was the accelerator, intended to shorten the time during which the material is not capable of supporting stress. Traditionally, accelerators have been made from calcium chloride, but today the trend is to use chloride-free additives to prevent reinforcing steel from corroding and thereby make constructions durable. The objective of this study was to evaluate the effects on the concrete of two types of accelerating admixture, using limestone aggregates, under warm sub-humid climate conditions. The applied methodology consisted of the measurement in the laboratory of some of the main properties of concrete in fresh and hardened states, in samples manufactured both with and without accelerators. The results showed that the accelerator without chloride was less effective than the one based on calcium chloride and that without doses of the accelerator, the effectiveness documented by the manufacturers was achieved.展开更多
文摘Additives are chemical compounds that are added to concrete during its manufacture to modify one or more of its properties. The first additive used in modern concrete was the accelerator, intended to shorten the time during which the material is not capable of supporting stress. Traditionally, accelerators have been made from calcium chloride, but today the trend is to use chloride-free additives to prevent reinforcing steel from corroding and thereby make constructions durable. The objective of this study was to evaluate the effects on the concrete of two types of accelerating admixture, using limestone aggregates, under warm sub-humid climate conditions. The applied methodology consisted of the measurement in the laboratory of some of the main properties of concrete in fresh and hardened states, in samples manufactured both with and without accelerators. The results showed that the accelerator without chloride was less effective than the one based on calcium chloride and that without doses of the accelerator, the effectiveness documented by the manufacturers was achieved.
