超高水材料充填回收浅埋大巷煤柱参数设计及围岩变形控制研究

Research on Coal Pillar Parameter Design and Deformation Control of Surrounding Rock in Shallow Buried Roadway by Filling Recovery with Ultra-high Water Material

超高水材料以超高含水率、易于输送、成本低和接顶效果好等优势应用于煤矿充填开采,但现场复杂的环境及施工经验不足常导致超高水材料出现泌水和不凝结等现象发生,从而影响采矿安全和施工效率。以内蒙古纳二矿浅埋煤矿回收大巷煤柱为工程背景,结合室内试验及现场监测,对超高水材料参数优化及围岩变形控制效果进行研究。结果表明:超高水材料拌合水温及AA料添加剂用量对材料的凝结时间、流动性、泌水率及强度等影响较大,20℃拌合水温及2%胶凝材料质量的AA料掺量能显著降低材料的泌水率和增强其强度。现场监测结果表明,最优参数下的材料充填开采后顶底板移近量较低,取得了良好的充填开采效果,在保障安全前提下极大地降低了生产成本。

Ultra-high water materials are used in coal mine filling mining with advantages of ultra-high water content,easy transportation,low cost and good roof connection effect.However,the complex environment and lack of construction experience often lead to the phenomenon of bleeding and non-condensation of ultra-high water materials,thus affecting the safety of mining and construction efficiency.Based on the coal pillar of the recovery roadway in the shallow coal mine of Na 2 Mine in Inner Mongolia as the engineering background,combined with the laboratory test and on-site monitoring,the optimization of ultra-high water material parameters and the effect of surrounding rock deformation control are studied.The results showed that the high water temperature and the amount of AA additive had great effects on the setting time,fluidity,bleeding rate and strength of the materials.The amount of AA additive in the 20℃mixing water temperature and 2%cementitious material could significantly reduce the bleeding rate and enhance the strength of the materials.The field monitoring results show that the displacement of roof and floor is lower after the material filling mining with the optimal parameters,which achieves a good filling mining effect and greatly reduces the production cost under the premise of ensuring safety.