大掺量高钙粉煤灰碾压混凝土性能研究

The performance of RCC with large volume high calcium fly-ash

通过采用消解、粉磨和外掺改性剂等技术措施,解决了大掺量(60%)高钙粉煤灰水泥浆体体积安定性问题。试验发现,大掺量高钙粉煤灰碾压混凝土抗压强度、轴拉强度和弹性模量比普通粉煤灰混凝土提高10%,极限抗拉应变两者相当。在28、90d时两者均表现为收缩,但前者干缩变形和自身体积变形只有后者的50%,这表明高钙粉煤灰具有补偿收缩的作用。研究证明,大掺量高钙粉煤灰碾压混凝土性能满足水工大体积混凝土的技术要求,且技术经济效益比普通粉煤灰混凝土优越。

The volume stability of the cement paste with large amount（above 60 percent）of high-calcium fly ash is solved by adopting measures of the slaking,milling and match admixture. The tests indicate that the axial compressive and tensile strength and the elastic module of the RCC with large amount of high-calcium fly ash improve 10 percent than the common fly ash concrete＇s, while their limited tensile strains are equivalent. 28days and 90 days both all express for the shrinkage,And the shrinkage-compensating action of the high-calcium fly ash is proved form the facts that the dry shrinkage and self-volume deformation of the concrete with large amount of high-calcium fly ash is only 50 percent of the common fly ash concrete＇s.The study proves that the performance of the RCC with large amount of high-calcium fly ash satisfy with the technique requirements of the large volume hydraulic concrete, and its technique and economic benefits are predominant than the common fly ash concrete＇s.