深部软岩巷道锚喷注强化承压拱支护机理及其应用

针对深部软岩巷道围岩总变形量大、收敛速率快、持续变形时间长以及支护系统损毁等矿压显现特点,分析了复杂应力场和高渗透压作用下的变形破坏机制,并结合深部巷道的"应力恢复、围岩增强、固结修复和主动卸压"控制原则,提出了集密集高强锚杆承压拱、厚层钢筋网喷层拱和滞后注浆加固拱于一体的锚喷注强化承压拱支护技术,并阐明其成拱及强化支护的机理。结合现场地质生产条件采用理论计算、数值模拟和工程类比法综合确定试验巷道围岩支护方案,并进行现场应用。现场实践表明,采用锚喷注强化承压拱支护技术后,巷道围岩总体变形量较小,围岩收敛率从扩刷修复前的2.6 mm/d降至0.56 mm/d,且支护系统亦无开裂损毁现象发生,实现了对深井软岩巷道的有效控制。

Anchor- spray- injection strengthened bearing arch supporting mechanism of deep soft rock roadway and its application

According to the strata behavior features of deep roadway with soft surrounding rock such as large amounts of total deformation，high convergence rate，long continuous time and support system damage，after having analyzed the deformation and failure mechanism affected in role of complicated stress field and osmolality，combining with control principles of deep roadway that are stress recovery，the surrounding rock enhancing，consolidation repair and active pressure relief，this paper put forward the anchor- spray- injection to strengthened bearing arch supporting technology integrated with high strength anchor bearing arch，thick steel mesh spray- up arch and lag grouting reinforcement arch，and clarified its arching and strengthening mechanism.The support program of test roadway was finally determined using the theoretical calculation，numerical simulation and engineering analogy method and combining field production and geological conditions，and the program was then put into field application.After the adoption of the anchor injection to strengthen bearing arch supporting technology，field practice shows that total roadway surrounding rock deformation amounts is small.Convergence rate of surrounding dropped from 2.6 mm/d before expansion brush repair to 0.56 mm/d.Besides，there is no cracking and damaged phenomena occurred in the support system.The above facts demonstrate that the technology achieves effective control of deep roadway with soft surrounding rock.