偏高岭土对模拟商混站强碱性废泥基人造石强度的影响

Influence of Metakaolin on Strength of Strong Alkaline Waste Mud-Based Artificial Stone in Simulated Commercial Concrete Mixing Plants

为实现商混站强碱性废泥的资源化利用,以实验室模拟的商混站强碱性废泥为对象进行人造石制备研究,探究了偏高岭土掺量及水灰比对人造石强度的影响规律及机理,并借助XRD和SEM分析了人造石的物相组成及微观形貌。结果表明:添加偏高岭土可以显著提高人造石的固结强度,当偏高岭土掺量为6%(质量分数)时抗压强度增幅最大,相对于对照组,14 d、28 d强度增长率分别为18.2%、20.3%;随着水灰比的增加,人造石抗压强度呈先增大后减小的趋势,14 d、28 d的抗压强度分别在水灰比为0.44、0.46时达到最大,分别为44 MPa、46 MPa。

In order to utilize the strong alkaline waste mud in commercial concrete mixing plants,the artificial stone was prepared from strong alkaline waste mud of commercial concrete mixing plants simulated in laboratory.The influences and mechanism of metakaolin content and water-cement ratio on the strength of artificial stone were studied in detail.The phase composition and microstructure of artificial stone were analyzed by XRD and SEM.The results show that the addition of metakaolin significantly increases the compressive strength of artificial stone.The compressive strength increases most when the content of metakaolin is 6%(mass fraction),and the strength growth rates at 14 d and 28 d are 18.2%and 20.3%,respectively.The compressive strength of artificial stone increases first and then decreases with the increase of the water-cement ratio.The compressive strength at 14 d and 28 d reaches the maximum when the water-cement ratio is 0.44 and 0.46,reaching 44 MPa and 46 MPa,respectively.