主要分析了粉煤灰品质指标对水泥抗裂性的影响。从胶凝材料浆体抗裂性的试验结果来看，粉煤灰烧失量、碱含量、SO3含量越低，掺粉煤灰水泥浆体的抗裂性越好。值得关注的是，适当增大粉煤灰的细度对提高水泥抗裂性有利。因此粉煤灰的品质应首先注重烧失量和需水量比，而细度不必过于苛求；碱含量对水泥抗裂性不利，宜进行限制。

In this paper, the effect of fly ash quality on the crack resistance was discussed. The lower the loss on ignition, alkali content and SO3 content of fly ash are, the better the crack resistance of the blended cement paste is. It is worthy to point out that properly increasing the fineness of fly ash is favorable for improving the crack resistance. Therefore the major quality indexes of fly ash are loss on ignition and water demand ratio, in the ?next place comes fineness. The alkali content of fly ash has disadvantage to the crack resistance of cement, so its quantity must be limited.