高级检索

煤矿冲击地压动静载危险源头分类、辨识与监测方法

Classification, identification and monitoring methods for static-dynamic stress hazard sources of rock burst in coal mine

  • 摘要: 煤矿冲击地压防治必须从源头抓起,其中冲击地压动静载危险源头分类、辨识与监测是实现冲击地压源头治理的重要前提。基于动静载叠加诱冲理论,总结了冲击地压的动静载危险源和作用方式,其中静载危险源主要分为地质沉积属性类、地质构造类和采掘应力集中类,共16种常见危险源;对冲击地压的作用方式主要包括煤岩性质不同使冲击发生的临界应力不同、巨厚坚硬岩层和断层运动产生强动载以及地质沉积微相的存在使煤岩体内静载应力升高3种方式。动载危险源主要分为震动波动载、受迫动载和炸药冲击动载3类;对冲击地压的作用方式主要包括使煤岩体内应力瞬时升高、强动载作用下冲击临界载荷降低及长时间动载作用下煤岩体和支护体累计损伤3种方式。针对静载冲击危险源头辨识问题,提出了基于地应力场反演的地质沉积静载危险源辨识方法,通过构建矿井地应力场反演模型并采用地应力实测数据矫正反演矿井地应力场分布状态,找出地质沉积静载危险区;提出了基于应力场CT反演技术的高静载危险源辨识方法,通过大范围长时间定期CT反演,找出高静载危险区。针对顶板岩层动载冲击危险源头辨识问题,提出了矿震关键层理论,构建了矿震关键层判别模型和方法。针对冲击静载危险源头监测,开发了主被动双源震动波一体化应力场监测技术,集成了主动和被动CT技术,实现了冲击静载危险源头实时、连续性的应力场反演分析。针对冲击动载危险源头监测,开发了井地一体微震监测技术,克服了传统微震监测技术垂直定精度差和冲击动载源头找不准的弊端,大幅度提高了微震监测精度和感知能力。基于现场应用,验证了上述技术方法的有效性,为冲击地压源头治理提供了参考。

     

    Abstract: The prevention and control of rock burst in coal mines should begin from the source, where classification identification and monitoring of static-dynamic stress hazard sources are essential prerequisites for rock burst source control. Based on the theory of rock burst induced by the superposition of static and dynamic stresses, its hazard sources and the associated action modes are summarized. Here static stress hazard sources contain 16 common types, which could be grouped into geological deposition attributes, tectonic structures and mining-induced stress concentrations. Their action modes are demonstrated in the following three ways: The critical stress of rock burst is different due to different coal-rock properties, strong dynamic loads can be generated due to the breakage of extremely thick and hard rock strata and the fault movement, and the static stress is elevated in coal-rock masses due to sedimentary microfacies. Dynamic stress hazard sources are divided into seismic wave loads, forced vibration loads and explosive impact loads. Their action modes comprise instantaneous stress increase in coal-rock masses, reduced critical stress of rock burst under strong dynamic loads, and cumulative damage to coal-rock and support systems under prolonged fatigued dynamic loading. For identification of static stress hazard sources, a geologic sedimentation abnormal identification method is proposed based on the in-situ stress field inversion, where the mine-scale stress distribution is inversed and calibrated with field measurements to locate geological static stress hazard zones. Besides, a stress field inversion technology is developed by a large-scale periodic seismic CT inversion to identify high static stress hazard zones. For identification of dynamic stress hazard sources from roof strata, the key stratum theory for mine tremors is proposed, and thereby the discriminant model and method for the key stratum of mine tremors are established. For the monitoring of static stress hazard sources, a stress field monitoring technology of active and passive dual-source seismic waves is developed. This technology has integrated both advantages of active and passive seismic CT technologies, which can realize real-time and continuous stress field inversion analysis for the static stress hazard sources of rock burst. For the monitoring of dynamic stress hazard sources, an underground-ground integrated microseismic monitoring system is developed, which has overcome the limitations of traditional microseismic monitoring, such as poor vertical location accuracy and difficulty in pinpointing dynamic stress hazard sources. This system has significantly enhanced the accuracy and sensitivity of microseismic monitoring. The effectiveness of above methods has been validated through field applications, which could provide valuable insights into source control of rock burst hazards.

     

/

返回文章
返回