基于地质力学测试的煤矿围岩特性分析

Analysis of coal mine surrounding rock characteristics based on geomechanical testing

  • 摘要:
    目的 为解决因巷道围岩地质力学特性认知不准确导致的巷道支护设计不合理、支护效果不佳及灾害频发等问题,
    方法 以西北某煤矿5号煤层为研究对象,在已掘巷道内布设三个测站,结合实测数据系统分析巷道围岩特性,通过钻孔窥视仪对围岩结构进行观测。
    结果 结果表明,顶板主要为坚硬砂岩,并据此选定地水力压裂试验段。采用水压致裂地应力测量仪对地应力场进行实测与分析,结果显示5号煤层地应力状态为σH>σv>σh,整体属于以构造应力为主的低应力区。钻孔触探法测试结果表明,顶板上部10 m内的砂岩平均强度为101.35 MPa,顶板类型为坚硬顶板;5号煤层煤体的平均强度为16.74 MPa。
    结论 上述原位试验数据为该煤层巷道支护设计提供了科学依据。

     

    Abstract: To tackle issues such as unreasonable roadway support design, poor support performance, and frequent disasters caused by inaccurate understanding of the geomechanical properties of roadway surrounding rock, the No. 5 coal seam of a coal mine in Northwest China was selected as the research object. Three monitoring stations were established in the excavated roadway, and the surrounding rock characteristics were analyzed based on field measurement data. Borehole endoscopy was used to observe the structure of the surrounding rock, revealing that the roof is mainly composed of hard sandstone, and the site for hydraulic fracturing tests was selected accordingly. In situ stress measurements using a hydraulic fracturing geo-stress meter indicated that the geo-stress state of the No. 5 coal seam is σH>σv>σh, which overall represents a low-stress zone dominated by tectonic stress. The results of the borehole probing tests indicate that the average strength of the sandstone within the upper 10 meters of the roof is 101.35 MPa, indicating that the roof is classified as a hard roof. The average strength of the coal body in the No. 5 coal seam is 16.74 MPa. The aforementioned in-situ test data provide a scientific basis for the support design of the roadway in the coal seam.

     

/

返回文章
返回