Properties and Engineering Applications of a New Goaf Grouting Filling Material

作者：Xiao Feng, XIA Chong, Sifeng Zhang, Chuangui Li, Hong-Kui Zhao, Jianfeng Wu, Mengjun Chen, Jia Yan · 发表于：Geofluids · 年份：2022 · DOI：10.1155/2022/6778076 · 被引用次数：7 · 研究领域：Grouting, Rheology, and Soil Mechanics、Microbial Applications in Construction Materials、Rock Mechanics and Modeling

In the treatment of goafs in traffic engineering, technical problems such as those related to large-volume grouting and the precise control of material properties are often encountered. To address these issues, we developed a new composite material comprising cement-fly ash-modified sodium silicate (C-FA-MS). The setting time, fluidity, unconfined compressive strength, and microstructure were varied for different proportions of cement-sodium silicate (C-S) slurry, cement-fly ash-sodium silicate (C-FA-S) slurry, and C-FA-MS slurry, and their performances were compared and analysed. The experimental results showed that the initial setting time of the slurry was the shortest when both the original sodium silicate volume ratio ( V S ) and modified sodium silicate volume ratio ( V MS ) were 0.2. The final setting time of the C-S and C-FA-S slurries tended to decrease but then increased with decrease in V S , while that of the C-FA-MS slurry increased with lower V MS . The fluidity of the C-FA-S and C-FA-MS slurries decreased with decrease in V S or V MS at different fly ash admixture ratios. The consolidation compressive strength of C-S increased with decreasing V S , while that of C-FA-S showed a considerable increase only when V S decreased from 0.4 to 0.2. Meanwhile, the compressive strength of the C-FA-MS concretions fi...