Roof pre-blasting to prevent support crushing and water inrush accidents

• Published in: International journal of mining science and technology 2012-05, Vol.22 (3), p.379-384
• Main Authors: Wang, Xiaozhen, Xu, Jialin, Zhu, Weibing, Li, Yingchun
• Format: Article
• Language: English
• Subjects: Key stratum; Roof pre-blasting; Support crushing and water inrush; Unconsolidated confined aquifer; 主关键层; 屋顶; 岩层结构; 承压含水层; 破碎; 突水事故; 突水灾害; 预爆破
• ISSN: 2095-2686
• DOI: 10.1016/j.ijmst.2012.04.016

Support crushing and water inrush when mining under an unconsolidated confined aquifer in the Q idong Coal Mine was prevented by roof pre-blasting. The mechanism and applicable conditions for this method have been studied. The results show that when an overburden structure that may cause support crushing and a water inrush accident exists the weakening of the primary key stratum, which thereby reduces its weighting step, roof pre-blasting is both feasible and effective. If the position of the primary key stratum can be moved upward to exceed 10 times the mining height the possibility of support crushing and water inrush disaster caused by key stratum compound breakage will be lowered. The overburden structure of the number 7121 working face was considered during the design of a technical proposal involving roof pre-blasting. After comprehensively analyzing the applicability of roof pre-blasting the resulting design prevented support crushing and water inrush disasters from happening at the number 7121 working face and laid a solid foundation for mining safely.