初始环境温度对聚羧酸系减水剂性能的影响

进行了未掺减水剂和掺两种不同功能型聚羧酸系减水剂在不同初始环境温度下的混凝土坍落度保持性能、凝结性能及强度性能的影响规律研究。结果表明,随着环境温度的升高,掺聚羧酸系减水剂混凝土的坍落度保持率均呈线性下降,未掺减水剂与掺聚羧酸系减水剂混凝土的初凝时间均呈线性缩短,聚羧酸系减水剂初凝时间差均是先减小后增大,未掺减水剂与掺聚羧酸系减水剂混凝土的1 d抗压强度均呈对数关系增长,28 d抗压强度则变化不明显,聚羧酸系减水剂的1 d抗压强度比均是呈降低趋势,28 d抗压强度比变化则均不明显。

EFFECT OF INITIAL AMBIENT TEMPERATURE ON PROPERTIES OF POLYCARBOXYLATE SUPERPLASTICIZER

The effect laws of the concrete performance with or without polycarboxylate superplasticizer are studied in this paper. These performances include slump retaining ability,setting performance and strength performance. The experiments indicate that the slump retaining ratio of the concrete with polycarboxylate superplasticizer is descendant linear relationship when the initial ambient temperature rises. The initial setting time of the concrete with or without polycarboxylate superplasticizer is shorten as initial ambient temperature rises. But the retarding time of the polycarboxylate superplasticizer first increases with the rising of the initial ambient temperature and then decreases,and the 1 day compressive strength of the concrete with or without polycarboxylate superplasticize increases in logarithmic relationship but the 28 days does not change significantly. At the same time,the 1 day compressive strength ratio of the polycarboxylate superplasticize is decreased but the 28 days is not obvious change as the rising of the initial ambient temperature.