基于人工干预的煤柱留巷围岩应力转移机制

For the problem of stress transfer mechanism of pillar protected roadway based on manual intervention, external factor (mining pressure field), inner factor(in-situ stress field) and inducement (manual intervention) will be researched. Based on in-situ rock stress measurement and surrounding rock stress monitoring for pillar protected roadway surrounding rock, the distribution characteristics of in-situ rock stress field and coal pillar rock stress are obtained. On the basis of physical and mechanical parameters of coal and rock mass and in-situ stress field, the large scale 3D similarity simulation test bed of pillar protected roadway with or without manual intervention are builded,with the surrounding rock stress monitoring of mining, the evolution law of surrounding rock stress filed with or without manual intervention are obtained. Based on the result of lab and field test, the numerical model of pillar protected roadway is establised, and the evolution law of surrounding rock stress filed with different cutting lines position, depth and angle are simulated with the numerical model. Based on the analysis of the acoustic emission monitoring data in the laboratory and the monitoring data of the surrounding rock stress of the pillar protected roadway, the project obtained the stress transfer mechanism of the roof rock by the manual intervention.

针对人工干预切顶卸压下煤柱留巷围岩应力转移机制不明的难题，从影响煤柱留巷围岩应力分布的外因（采动应力场）、内因（原岩应力场）和诱导因子（人工干预切顶卸压）入手开展研究。通过现场原岩应力测试和煤柱留巷围岩应力监测，获取矿井原岩应力场分布特征和留巷围岩应力场分布规律；基于现场煤岩体物理力学参数测试和原岩应力场分布规律，建立有、无人工干预切顶卸压条件下煤柱留巷围岩大型三维相似模拟试验台，开展随回采过程的围岩应力监测，获得有、无人工干预切顶卸压条件下煤柱留巷围岩应力场演化规律；在实验室和现场测试结果基础上，建立经过校验的煤柱留巷围岩数值计算模型，计算不同切顶线位置、深度、角度等参数下人工干预切顶卸压煤柱留巷围岩的应力场演化特征，结合实验室声发射监测数据和现场切顶卸压煤柱留巷围岩应力监测数据分析，得出人工干预切顶卸压煤柱留巷围岩应力转移机制。

煤柱留巷是我国井工煤矿回采巷道常用的巷道布置形式，实践证明，在多重动压作用下煤柱留巷发生多重应力叠加、煤柱裂隙发育与突然扩增失稳，导致煤柱留巷变形大、巷道维护困难，安全与有效利用成为亟待解决的科学难题。课题以山西典型厚煤层煤柱留巷为研究对象，以“煤层开采应力传递-煤柱留巷应力变化-围岩裂隙演化与破坏特征-人工干预顶板垮落特征-人工干预煤柱留巷围岩应力演化-卸压与支护煤柱留巷综合控制”为技术路线，采用现场测试与试验、实验室研究、数值计算与分析相结合的研究方法，分析了煤柱留巷变形的时间和空间特征，揭示了煤柱留巷人工干预的时机与范围；得出了人工干预下人工裂隙的扩展规律与围岩应力转移的关系；提出了煤柱留巷人工干预围岩应力转移与高刚度支护的综合控制方法。煤柱留巷是我国广泛存在的巷道布置方法，研究具有重要的理论意义和广泛的应用前景。