摘   要：研究了粉煤灰掺量、粗骨料孔隙率、砂率、外加剂等因素对低强度等级自密实混凝土工作性能的影响规律。结果表明：适当降低水泥用量，增加粉煤灰掺量及总胶材用量，可有效改善自密实混凝土的工作性能；当大、小石子比例为7:3时，骨料的孔隙率最低，混凝土的工作性能最好；使用细砂可明显提高混凝土的黏聚性，研究发现细砂的砂率为48%时，混凝土的工作性能最好；合理使用具有黏度改性型外加剂可使混凝土在较大流动度的状态下不出现离析、泌水现象。

Abstract：The Influence of fly ash dosage, coarse aggregate porosity, mortar ratio and admixture on the workability of low grade self compacting concrete was studied. The results show that the workability of low grade self compacting concrete can be improved by properly reducing the amount of cement and increasing the content of fly ash and the amount of total cementitious materials; when the ratio of large stones to small stones is 7:3, the aggregate porosity is the lowest, and the concrete has the excellent workability; using fine sand can obviously improve the cohesiveness of concrete. It is found that concrete has the best workability when the sand ratio is 48%. adding a viscosity modifying admixture can make the concrete have high workability and no the phenomenon of bleeding or segregation.