矿渣粉大量替代水泥对高效减水剂作用的影响

Effect of Large-volume Addition of Slag Powder on the Actions of Superplasticizer

对比了矿渣粉、Ⅱ级粉煤灰、沸石粉和硅灰等4种活性掺合料分别以不同比例等量替代水泥后对减水剂塑化效果和浆体流动度保持性的影响.试验结果表明,与其它3种掺合料相比,掺矿渣粉有助于增强减水剂塑化效果和改善浆体流动度保持性.对比矿渣粉与高效减水剂单掺和双掺情况下新拌混凝土的性能,表明矿渣粉还具有一定的辅助减水效应,且有助于降低混凝土的坍落度损失.另外,还对产生有关试验现象的机理进行了分析.

The effects of mineral admixtures (slag powder, fly ash, zeolite powder and silica fume) at different replacement ratios on the dispersing capability of superplasticizer and fluidity preservation of paste were experimentally investigated. The results indicate that compared with the other three mineral admixtures, slag powder benefits to the dispersing efficiency of superplasticizer and to the fluidity preservation of paste. The tests on the properties of fresh concrete added with superplasticizer or/and slag powder were also studied. The results show that slag powder not only has an assisted waterreducing action, but also is helpful to reduce slumploss of concrete. The reasons leading to the test phenomena are explained in the paper.