千米深井沿空留巷复合充填体研制与应用

Development and application of composite filling body in gob-side entry retaining with 1000m-plus deep coal mine

针对千米深井沿空留巷存在的问题,以山东某矿为试验场所,开展了沿空巷旁复合材料充填试验及其应用的研究。通过对沿空留巷覆岩结构模型和岩层运动的分析,认为留巷围岩结构要经历4个主要动压阶段:巷旁围岩破碎圈扩大阶段、不对称结构形成阶段、蠕变与稳定阶段以及二次回采超前影响阶段;根据岩层运动及矿压理论建立了巷旁充填体最大压缩量和矸石砖的最小抗压强度计算模型,得出充填体最大压缩量和最小强度分别为0.3 m和6 MPa;基于此提出了基于复合充填材料的分段分级施工、承载理论,并进行了主副墙体的参数和性能设计;最后,研究了主墙体矸石砖的制作过程,包括配比的优化、生产的工艺流程等参数。该矿工程实践表明,沿空巷旁复合材料(主副墙体)充填技术能够适应顶板岩层的运动规律,发挥了主副墙体的各自功能,满足支撑顶板、维护巷道稳定等需求,达到了预期效果。

The aim of this work is to study the gob-side entry retaining problem using composite filling material in the 1000 m-plus deep coal mine. And the work is tested in some coal mine in Shandong. According to the structural mechanical model of gob-side entry retaining overlying strata, the rock mass structure has undergone dynamic pressure in four stages： expending stage of fragmentation circle radius, formation stage of asymmetric structure, creep and steady stage, and secondary recovery stage. Accord- ing to the underground pressure theory and mine pressure theory, a calculation model about construction methods was built, the maximum compression value of filling wall of 0.3 m and the minimum compres- sive strength of coal gangue brick of 6 MPa were worked out, and the sectional and classification prin- ciple of backfill walls＇ bearing and production theory about composite wall was put forward, including the production method, material mixture ratio and construction methods. Based on the above investiga-tion and the geological conditions of the coal mine, the support body using composite materials dis- played their function respectively and met the need of roof stratum movement. And the late result has shown that this technology achieves the desired results.