赤泥激发粉煤灰充填材料设计及激发机理研究

Development of Red Mud Activated Fly Ash-based Backfilling Material and Its Activation Mechanism

利用赤泥碱性激发粉煤灰原理,制备赤泥激发粉煤灰充填材料,研究其流动度、力学性能、水化产物、孔结构和微观形貌。结果表明,掺入赤泥可提高粉煤灰-水泥体系的碱度,加速胶凝材料的早期水化反应,促进C-S-H凝胶、钙矾石、半碳铝酸钙等水化产物生成;同时,赤泥具有颗粒细小、比表面积大等特点,提供微填充效应,能够重塑孔结构,降低大孔、有害孔的比例,提升材料强度。

The feasibility of using high volume red mud as alkali source was investigated to improve the performance of fly ash based backfilling materials.The effect of red mud on the properties of fly ash based backfilling materials were characterized in terms of the flowability,strength development,reaction products,pore structure,and microscopic morphology,etc.The experimental results show that the incorporation of red mud not only accelerates the hydration of fly ash due to its high alkalinity,but also promotes the generation of the hydration products such as C-S-H,ettringite and hemicarbonate.The red mud also acts as micro-filler which refines the pore structure,and reduces the pore size and the amount of harmful pores due to its fine particle size.