深部冲击地压巷道锚杆支护作用研究与实践

以义马常村煤矿深部冲击地压巷道为工程背景,介绍了深部冲击地压巷道围岩地质力学参数分布特征,分析了冲击地压巷道围岩变形与破坏特征及主要影响因素,揭示出锚杆支护对冲击地压巷道变形的本质作用是保持围岩完整性,在围岩中形成支护应力场,降低应力集中系数,改善巷道围岩应力分布,充分发挥围岩的抗冲击能力。提出冲击地压巷道支护形式选择原则,介绍了高冲击韧性锚杆支护材料力学性能及锚杆支护参数设计方法。针对常村煤矿21220下巷条件,提出以全长预应力锚固、高强度、高冲击韧性锚杆与锚索支护为主,以金属支架为辅的复合支护方式,并进行了井下工业性试验。矿压监测数据表明,该种支护方式与围岩的整体抗冲击能力强,能够有效控制深部冲击地压巷道变形与破坏。在冲击能量影响下,锚杆、锚索受力特征明显不同于普通巷道,呈波浪状或锯齿状变化趋势。

Rock bolting performance and field practice in deep roadway with rock burst

The geomechanics parameter distribution features of rocks surrounding a deep roadway with rock burst in the Changcun Coal Mine of Yima coal mining district,China were introduced,and the deformation and damage characteristics and the main affecting factors of rocks surrounding the deep roadway with rock burst were analyzed.The intrinsic actions of rock bolting to roadway deformation with rock burst were revealed,which include keeping the integrity of surrounding rocks,forming bolting stress fields in surrounding rocks,reducing the stress concentration factors,improving stress distribution around surrounding rocks,and enhancing the anti-impact ability.In addition,the principles in selecting roadway support patterns with rock burst were put forward,the mechanical performances of rock bolt materials with high impact toughness,and the design method of rock bolting parameters were explained.The combined support pattern,i.e.,taking rock bolts and cables with high strength and high impact toughness,full length encapsulation with pretension as main supports,steel arches as supplementary supports,was presented to support the maingate No.21220 in the Changcun Coal Mine,and the underground test was carried out.The monitoring data pointed out that: the combined support pattern proposed,which unites with surrounding rocks as a whole and has strong anti-impact ability,can effectively control the deformation and damage of rocks surrounding the deep roadway with rock burst.The loading features of rock bolts and cables under the action of impact energy are different from those in common roadways,which present a wavy or zigzag variation tendency.