Zhang Peter, Gearhart Dave, Van Dyke Mark, Su Daniel, Esterhuizen Essie, Tulu Berk
NIOSH, Pittsburgh Mining Research Division (PMRD), Pittsburgh, PA 15236, USA.
Department of Mining Engineering, West Virginia University, Morgantown, WV 26505, USA.
Int J Min Sci Technol. 2019 Jan;26(1):27-33. doi: 10.1016/j.ijmst.2018.11.020.
Roof falls in longwall headgate can occur when weak roof and high horizontal stress are present. To prevent roof falls in the headgate under high horizontal stress, it is important to understand the ground response to high horizontal stress in the longwall headgate and the requirements for supplemental roof support. In this study, a longwall headgate under high horizontal stress was instrumented to monitor stress change in the pillars, deformations in the roof, and load in the cable bolts. The conditions in the headgate were monitored for about six months as the longwall face passed by the instrumented site. The roof behavior in the headgate near the face was carefully observed during longwall retreat. Numerical modeling was performed to correlate the modeling results with underground observation and instrumentation data and to quantify the effect of high horizontal stress on roof stability in the long-wall headgate. This paper discusses roof support requirements in the longwall headgate under high horizontal stress in regard to the pattern of supplemental cable bolts and the critical locations where additional supplemental support is necessary.
当存在软弱顶板和高水平应力时，长壁工作面运输巷可能会发生冒顶。为防止在高水平应力下运输巷冒顶，了解长壁工作面运输巷对高水平应力的岩层响应以及补充顶板支护的要求非常重要。在本研究中，对处于高水平应力下的长壁工作面运输巷进行了仪器监测，以监测煤柱中的应力变化、顶板变形以及锚索载荷。当长壁工作面通过仪器监测区域时，对运输巷的状况进行了约六个月的监测。在长壁工作面回撤期间，仔细观察了靠近工作面处运输巷的顶板行为。进行了数值模拟，将模拟结果与地下观测和仪器监测数据相关联，并量化高水平应力对长壁工作面运输巷顶板稳定性的影响。本文讨论了在高水平应力下长壁工作面运输巷的顶板支护要求，涉及补充锚索的布置方式以及需要额外补充支护的关键位置。
