全尾砂新型胶凝材料的胶结作用

Cementing Action of Neotype Whole Tailing Cementitious Material

关键词:  全尾砂  水淬高炉矿渣  新型胶凝材料  复合激发剂  充填体

Key words:  whole tailing  water quenching blast furnace slag  neotype cementitious material  composite activator  backfilling body

摘要:

以水淬高炉矿渣为主要材料，石灰加脱硫石膏为复合激发剂，添加少量外加剂，制备了全尾砂新型胶凝材料.探讨了不同掺量复合激发剂对全尾砂新型胶凝材料充填体抗压强度的影响；通过X射线衍射分析和扫描电镜分析研究了全尾砂新型胶凝材料水化产物的组成和微观形貌.结果表明：当全尾砂新型胶凝材料中石灰、脱硫石膏、外加剂、水淬高炉矿渣的掺量（质量分数）分别为40%，17.5%，0.5%，78.0%，胶砂比（质量比）为1∶8，充填料浆浓度（质量分数）为68%时，全尾砂新型胶凝材料充填体28d抗压强度可达到3.09MPa，是充填料浆浓度、胶砂比和外加剂掺量相同条件下42.5R水泥充填体28d抗压强度的7.2倍.在全尾砂胶结充填中全尾砂新型胶凝材料能完全取代水泥作为胶凝材料.全尾砂新型胶凝材料的主导水化产物为AFt晶体和无定形C S H凝胶.

Abstract:

Water quenching blast furnace slag was chosen to produce a neotype whole tailing cementitious material with using lime and desulphurized gypsum as composite activator and adding small amount of admixture. The effect of different use level of composite activator on the compressive strength of neotype whole tailing cementitious material backfilling body was investigated. Compositions and microstructures of hydration products of neotype whole tailing cementitious material were studied by X ray diffraction and scanning electron microscopy. Results show that as the mix proportion(by mass) of the cementitious material is 4.0% lime, 17.5% desulphurized gypsum, 0.5% admixture, 78.0% water quenching blast furnace slag, the mass ratio of the cementitious material to whole tailing being 1∶8 and the concentration(by mass) of backfilling slurry being 68%, the compressive strength of the neotype whole tailing cementitious material backfilling body is 3.09MPa when cured for 28d, which is 7.2 times that of 42.5R cement backfilling body at the same concentration(by mass) of backfilling slurry, same mass ratio of the cementitious material to whole tailing and same mass proportion of admixture. The neotype whole tailing cementitious material can replace traditional cement in whole tailing backfilling. Hydration products of the neotype whole tailing cementitious material are mainly ettringite crystal and C S H gel.