缓凝剂对C50低氯离子混凝土性能的影响研究

摘要

The influence of different kinds of retarder on the workability,volume change,strength,and hydration heat of C50 low chloride ion concrete were studied by using three kinds of retarders.Based on the design requirements of C50 high performance concrete,the content of chloride ion was controlled below 0.06%by adjusting and optimizing the mix proportion and the hydration heat was reduced by mixing right amount of fly ash.The results show that the fluidity loss can be effectively reduced and at the same time early volume deformation of concrete can be lowered without adverse effects on the late strength.Among the three kinds of retarders,the retarding effect of citric acid is stable.%采用三种缓凝剂来研究不同缓凝剂对C50低氯离子混凝土工作性、体积变化、强度和水化热的影响。基于C50高性能混凝土的设计要求，通过调整优化原料配比来实现混凝土中的氯离子含量在0.06%以下，并通过掺加适量的粉煤灰以达到降低水化热的目的。研究结果表明：掺加缓凝剂可以有效的减少混凝土的经时损失，同时降低混凝土早期体积变形，并对后期强度无不良影响。三种缓凝剂中，柠檬酸的缓凝效果比较稳定。