纤维缓凝剂对混凝土力学性能的试验分析

Experimental analysis of mechanical properties of concrete with fiber retarder

缓凝剂能够减缓混凝土的凝结时间,从而为施工带来便利,但过量的掺入会对混凝土的坍落度和抗压强度带来影响。以棉纤维与碳纤维作为缓凝剂,调节缓凝剂的掺入量来分析其对凝结时间、坍落度以及抗压强度的影响。试验结果表明:两种缓凝剂均能够延长凝结时间,并能够很好地抑制坍落度的损失;随着缓凝剂掺量的增加,混凝土抗压强度先上升而后逐渐降低。建议碳纤维缓凝剂的掺量小于0.2%,棉纤维缓凝剂掺量小于0.05%。

Retarder can slow down the setting time of concrete and bring convenience to construction, but excessive mixing will affect the slump and compressive strength of concrete. Therefore, cotton fibers and carbon fibers are used as retarders, and the amount of retarders is adjusted to analyze their effects on setting time, slump and compressive strength. The results show that two retarders could prolong the setting time, and both kinds of retarders could restrain slump loss well, With the increase of the content of retarder, the compressive strength of concrete increases first and then decreases gradually. It is suggested that the content of carbon fiber retarder should be below 0.2% and that of cotton fiber retarder should be below 0.05%.