赤泥-矿渣-石膏-少熟料胶凝材料的初期水化过程

Early Stage Hydration Process of Cementitious Material Prepared with Red Mud,Slag,Gypsum and Small Smounts of Cement Clinker

赤泥-矿渣-石膏-少熟料胶凝材料在胶结充填过程中表现出良好的保水性及早强、高强等性能,可以作为充填专用胶结剂。本文综合净浆试块的凝结时间、强度发展以及扫面电镜下的微观结构,分析了材料的初期水化过程,并采用XPS研究了不同元素之间旧组合分解和新组合的形成。结果表明水化3 h时体系生成Ca(OH)2和凝胶类物质,这些水化产物使得浆体凝结硬化。4 h后矿渣中的部分硅氧四面体参与反应,缩聚成了聚合度较高的硅酸盐矿物,净浆试块产生强度。水化6 h后,S2 p3/2的结合能大幅增长,体系生成了较多的硫酸盐矿物,它们对强度的发展起到了较大作用。

The cementitious material prepared with red mud, ground granulated blast furnace slag （GGBS）, flue gas desulfurization gypsum （FGDG） and a small amount of cement clinker obtained good performances in water-retention, early strength and high strength when it used for cemented backfilling This material can be used as special cement for backfilling. The early stage hydration of the material was analyzed through the setting time, strength development and microstrueture. The decomposition of old system and the formation of the new mineral were also studied by X-ray photoelectron spectroscopy （XPS）. Results show that Ca（OH） 2 and gels formed at 3 h after hydration, resulting in the setting and hardening for the cement paste. The samples obtained strength at 4 h, which is attributed to the formation of silicates with higher polymerization degree, which condensed from oxygen-silicon tetrahedron. At 6 b, the binding energy of S2 P3/2 increased suddenly, and some sulfate minerals formed, which made a great contribution to the rise of strength.