张海波, 孙会婷, 柴虎成,等.硅灰掺量对泡沫充填材料性能和微观结构的影响[J].河南理工大学学报（自然科学版）,2025,44(4):188-196.

ZHANG H B, SUN H T, CHAI H C, et al. Effect of silica fume content on the properties and microstructure of foam filling materials [J]. Journal of Henan Polytechnic University (Natural Science) , 2025, 44(4): 188-196.

硅灰掺量对泡沫充填材料性能和微观结构的影响

张海波, 孙会婷, 柴虎成, 胡毅康, 周运通, 谢佰恩, 田艳超

河南理工大学 材料科学与工程学院，河南 焦作，454000

摘要: 目的 充填材料泡沫混凝土孔隙率高，导致强度显著降低。 方法 本文使用硅灰取代普通硅酸盐水泥制备高强低密泡沫混凝土（silica fume- ordinarily portland cement， SF-OPC），研究硅灰不同掺量（0%，5%，10%，15%，20%）对SF-OPC样品的流动度、凝结时间、抗压强度、干密度等宏观性能的影响，并结合低场核磁技术测试孔隙结构，纳米压痕表征硬化浆体骨架硬度，X射线衍射分析水化产物的物相，扫描电镜分析微观物相结构。 结果 结果表明，随着硅灰掺量增加，浆体流动度先增加后降低，凝结时间不断减少，SF-OPC试样强度先增加后减小；硅灰掺量为5%时，流动度最大，为223.1 mm；硅灰掺量为15%时，SF-OPC试样强度最高，3，7，28 d龄期强度分别为3.8，4.2，4.9 MPa，与对照组相比分别提高123.5%，100.0%，75.0%，宏观孔比例降低75.8%，纳米孔比例增加208.4%。 结论 掺入硅灰可以促进低钙型C-S-H凝胶的形成，有效改善SF-OPC的孔隙结构分布，提高浆体骨架结构硬度，微观结构更加致密。相同发泡倍数下，硅灰可显著提高SF-OPC强度，适于制备煤矿高冒区高强低密泡沫充填材料，同时为煤矿采空区充填防火材料研究提供借鉴。 

关键词:充填材料;泡沫混凝土;硅灰;孔隙结构;火山灰效应

doi: 10.16186/j.cnki.1673-9787.2023120020

基金项目:国家自然科学基金资助项目（U1905216）；国家重点研发计划项目（2017YFC0603004）

收稿日期:2023/12/08

修回日期:2024/02/18

出版日期:2025/06/19

Effect of silica fume content on the properties and microstructure of foam filling materials

Zhang Haibo, Sun Huiting, Chai Hucheng, Hu Yikang, Zhou Yuntong, Xie Baien, Tian Yanchao

School of Materials Science and Engineering， Henan Polytechnic University， Jiaozuo 454000， Henan，China

Abstract: Objectives The high porosity of cement-based foam concrete used as a filling material significantly reduces its strength. Methods In this study， silica fume （SF） was used to partially replace ordinary Portland cement （OPC） to prepare a high-strength， low-density foam concrete （SF-OPC）. The effects of different SF replacement levels （0%， 5%， 10%， 15%， and 20%， by weight） on the fluidity， setting time， compressive strength， and dry density of SF-OPC were systematacially investigated. Additionally， low-field nuclear magnetic resonance （LF-NMR） was employed to characterize pore structure， nanoindentation was used to evaluate the hardness of the hardened slurry skeleton， X-ray diffraction （XRD） was applied to analyze hydration products， and scanning electron microscopy （SEM） was conducted to observe microstructural morphology. Results The results showed that increasing SF content initially improved the fluidity of the slurry and then caused a decline， while the setting time decreased continuously. The compressive strength of the specimens first increased and then decreased. The maximum fluidity （223.1 mm） was observed at 5% SF content， whereas the highest compressive strength was achieved at 15% SF content， with 3-， 7-， and 28-day strengths of 3.8 MPa， 4.2 MPa， and 4.9 MPa， respectively—representing increases of 123.5%， 100.0%， and 75.0% compared to the control group. The proportion of macropores decreased by 75.8%， while the proportion of nanopores increased by 208.4%. Conclusions The addition of silica fume promoted the formation of low calcium C—S—H gel， effectively optimizing the pore structure distribution， enhancing the structural hardness of the slurry skeleton， and resulting in a denser microstructure. Under the same foaming ratio， SF significantly improved the compressive strength of SF-OPC foam concrete. This makes it a promising material for high-strength， low-density backfilling applications in coal mine caving zones and offers a useful reference for fire prevention and control materials used in mine goafs. 

Key words: filling material; foam concrete; silica fume; pore structure; pozzolanic effect