新型早强剂对混凝土性能的影响研究

New hardening accelerator affecting concrete properties

以晶种、高价阳离子硫酸盐和羟基羧酸复合制成的新型早强剂,用其拌制的混凝土的工作性好,可以显著提高早期强度,降低坍落度损失和泌水,减少干缩。新型早强剂对水泥的适应性强,在低温下具有很好的早强效果,混凝土中水的冰点下降达2.6℃。XRD和SEM显示掺加新型早强剂的混凝土早期水化产物增多,结构密实,其抗渗、抗冻性能提高,耐久性好。

The new hardening accelerator consists of the crystal seed, the high valence cation sulfate and hydroxycarboxylic. When the new hardening accelerator was added into concrete, the concrete workability was improved, the early strength was improved markedly, the slump-loss and bleeding was reduced, and the shrinkage was decreased. The new hardening accelerator has a good compatibility with cement. The effect of early strength is obvious at low temperature. The water freezing point inside the concrete fall 2.6℃. The experimental results of XRD and SEM demonstrated that the more hydration products are formed during the early period, the structure of concrete becomes dense, the concrete frost-resistance and impermeability are improved, and the durability is better.