浅埋深薄基岩巷道锚注加固技术研究

Bolt grouting reinforcement technology for shallow buried thin bedrock roadway

针对红柳林煤矿浅埋深薄基岩巷道顶板锚固力低的难题,分析了风化基岩分布特征以及矿物成分,开展了薄基岩注浆加固试验,分析了薄基岩巷道注浆加固机理,提出了巷道锚注加固技术方案,并开展了井下工程实践,分析了工程应用效果。结果表明:风化薄基岩黏土矿物成分含量高,增大了顶板岩体软化和膨胀变形,影响巷道围岩稳定性;井下注浆充填了风化基岩裂隙,封堵了顶板水渗流通道,提高了顶板完整性,增大了薄基岩层的抵抗破坏的能力;通过锚索注浆达到了较好的注浆固结效果,锚杆(索)初期受力缓慢增大,随后基本保持稳定,锚杆受力55~67 kN,锚索受力92 kN左右,顶板离层量3 mm左右,巷道围岩变形明显减小,达到了较好的巷道支护效果,表明锚注加固技术可有效解决浅埋深薄基岩巷道变形控制难题。

Aiming at the low roof anchoring force in shallow thin bedrock roadways in Hongliulin Coal Mine,the distribution characteristics and mineral composition of weathered bedrock were analyzed,and grouting reinforcement tests for thin bedrock roadways were conducted.The grouting reinforcement mechanism for thin bedrock roadways was analyzed,and a technical scheme for roadway bolting and grouting reinforcement was proposed.Underground engineering practice was conducted,and the effect was analyzed.The results show that the weathered thin bedrock has a high content of clay minerals,which increases the softening and swelling deformation of the roof rock mass,and affects the stability of the roadway surrounding rock;underground grouting fills the fissures of weathered bedrock,blocks the seepage passage of roof water,improves the integrity of the roof,and increases the resistance to damage of the thin bedrock layer;through bolt cable grouting,a favorable grouting consolidation effect was achieved.The initial stress of the bolt(cable)slowly increased,and then it remained basically stable.The bolt stress was 55~67 kN,the cable stress was about 92 kN,and the roof separation amount was about 3 mm.The deformation of the surrounding rock of the roadway was significantly reduced,achieving favorable roadway supporting effect,indicating that the bolt grouting reinforcement technology can control the deformation control in shallow thin bedrock roadways.