地面定向钻孔预注浆加固技术在断层带巷道围岩控制中的应用

Application of Ground Directional Drilling Pre-grouting Reinforcement Technology in Surrounding Rock Control of Fault Zone Tunnels

针对巷道通过地质构造带时围岩破碎程度大,节理裂隙发育,常规支护手段难以有效控制巷道围岩变形,极易引发安全事故现状。本文以芦子沟煤矿东翼大巷为工程背景,分析了东翼大巷地质条件及穿断层掘进特征,提出了地面定向预注浆加固实施方案,通过实验验证了地面注浆加固技术的有效性。同时,基于断层地质构造对巷道围岩稳定性的影响特征,提出了“锚架+锚注+锚索梁补强”穿断层联合支护技术,并结合现场情况进行了工业性试验。试验结果表明:穿断层联合支护技术能有效保证巷道在穿断层过程中围岩的稳定控制,巷道围岩变形量得到有效控制,顶底板最大移近量约为118.3 mm,两帮最大移近量约为78.4 mm,支护形式安全可靠。

In response to the high degree of rock fragmentation and the development of joint fissures when tunnels pass through geological structural zones,conventional support methods are difficult to effectively control the deformation of tunnel rock,which can easily lead to safety accidents.This article takes the east wing roadway of Luzigou Coal Mine as the engineering background,analyzes the geological conditions and characteristics of fault crossing excavation in the east wing roadway,proposes a ground directional pre grouting reinforcement implementation plan,and verifies the effectiveness of ground grouting reinforcement technology through experiments.At the same time,based on the characteristics of the influence of fault geological structures on the stability of roadway surrounding rock,the"anchor frame+anchor injection+anchor beam reinforcement"fault crossing joint support technology was proposed,and industrial tests were conducted in combination with the on-site conditions.The experimental results show that the combined support technology for crossing faults can effectively ensure the stable control of the surrounding rock during the process of crossing faults,and the deformation of the surrounding rock in the tunnel is effectively controlled.The maximum displacement of the roof and floor is about 118.3 mm,and the maximum displacement of the two sides is about 78.4 mm.The support form is safe and reliable.