采用机制砂配制自密实混凝土，通过试验研究分析粉煤灰掺量对自密实混凝土收缩性能的影响。通过固定水胶比等配合比参数，以粉煤灰掺量为变量，分别实验测试得到了掺0%、20%和43%三个水平的粉煤灰条件下机制砂自密实混凝土的干燥收缩、自收缩及温度收缩的变化规律。试验结果表明：掺加粉煤灰可减少机制砂自密实混凝土的收缩，且掺量低于20%时其对机制砂自密实混凝土的自收缩与干燥收缩的控制效果有限，而当粉煤灰掺量增加到40%左右时，其对机制砂自密实混凝土收缩的抑制作用显著。
The mechanism sand is used to make up self-compacting concrete, and the effect of fly ash content to the shrinkage of self-compacting concrete is researched by laboratory experiments. Water to binder ratio is fixed, and the fly ash content is variable at three levels, which are 0%, 20%, 40%. The change regulation of dry-shrinkage, self-shrinkage, temperature-shrinkage with the above three levels is obtained. The result shows that the fly ash can eliminate the shrinkage of self- compacting concrete. The elimination effect is limited when the fly ash content is 20%, and when the content of fly ash reaches to 40%, the elimination effect is significant.
