On August 2, 2019, a catastrophic rockburst disaster occurred in Tangshan mine, causing death of 7 miners. After the investigation, the coal mine is facing reproduction. Taking the 0291 panel as the engineering background, this paper studies the coal seam blasting pressure relief and ground stress monitoring technology in working face retreat. During the roadway development and working face excavation, coal seam blasting was adopted to transfer the high ground stress of coal seam to the deep ground of the coal body. The blasting operation is presented in detail in this paper. In the working face retreat stage, drilling powder method, hydraulic shield resistance monitoring, roof displacement, and vibration monitoring methods are implemented. The results show that the pressure relief range of coal seam is 4–12 m in the coal mass after blasting. The shield working resistance is stable at 20–30 MPa. The range of relative displacement of the roof is about −1.0 to 2.5 mm, and the maximum vertical vibration velocity is in the range of 7–11 cm/s, up to 12 cm/s. The measured parameters are acceptable, so it is concluded that 0291 panel can be safely mined. This study provides a reference for the coal seam blasting design for rockburst coal mine and provides a technical means for the analysis of pressure release effect and dynamic pressure monitoring during working face retreating.

中文翻译：

---

煤层长钻孔爆破技术及高爆破长壁板泄压效果综合评价方法

2019年8月2日，唐山矿山发生特大岩爆灾害，造成7名矿工死亡。经查，该煤矿面临再生产。以0291面板为工程背景，研究了工作面后退煤层爆破卸压及地应力监测技术。在巷道开发和工作面开挖过程中，采用煤层爆破，将煤层的高地应力传递到煤体深部。本文详细介绍了爆破作业。在工作面后退阶段，采用钻粉法、水力盾构阻力监测、顶板位移、振动监测等方法。结果表明，爆破后煤体中煤层的卸压范围为4～12 m。屏蔽工作电阻稳定在20-30 MPa。屋顶的相对位移范围约为-1.0～2.5 mm，最大垂直振动速度在7～11 cm/s范围内，最高可达12 cm/s。测得的参数是可以接受的，因此可以得出0291面板可以安全开采的结论。该研究为岩爆煤矿的煤层爆破设计提供了参考，为工作面后退压力释放效果分析和动压监测提供了技术手段。