基于围压恢复加固理论的软岩巷道支护机理研究

以首云铁矿为工程背景,针对其矿岩水理性差、稳定性差等特点,采用室内试验、理论分析、现场实践和监测分析等综合方式,提出了长短锚杆结合的锚喷网支护,配合强化的护表结构和支架的联合支护方式。结果表明,临时支护有效地封闭了围岩,避免了开挖巷道的进一步破坏,长短锚杆相结合充分利用了深部围岩稳定性,将开挖区应力进行了转移,以钢筋条带和喷浆进行的护表结构对上部围岩提供了有力支撑。监测表明,巷道表面位移累计量不超过30mm,有效地抑制了巷道变形,所得结论对软破岩巷道支护具有重要的借鉴意义。

Study on the mechanism of soft rock tunnel support based on the theory of confining pressure restored reinforcement

Based on the engineering background of Shouyun Iron Mine, the characteristics of bad hydrophysical and poor stability are considered. With the comprehensive ways including laboratory test, theoretical analysis, field practice and monitoring analysis, the bolting and shotcrete wire using long-short bolts is put forward, which is also coordinated with strengthening surface structure and metallic stent. It turned out that the temporary support effectively closed the surrounding rock, avoiding the further damage of excavation. The combination of long-short bolts system makes full use of the stability of deep surrounding-rock, which transferred the stress of the excavation region to the deeper rock masses. The surface structure of steel strip and shotcrete protect the steadiness of upper rock. Monitoring result indicates that the roadway accumulated deformation can be controlled within 30 mm. It effectively suppresses the deformation of roadway, so the conclusion in soft rock roadways support can be used for reference.