后云台山隧道地应力测试分析与岩爆防治措施

Analysis of the Crustal Stress Measurement and Our Rock-Burst-Preventing Measures for the Houyuntai Mountain Tunnel

高地应力是一种常见的隧道地质灾害,在施工前准确掌握隧道穿越段的工程地质状况及地应力状态至关重要。针对后云台山隧道施工中洞室围岩发生"脆响"及掌子面后方初期支护喷射混凝土开裂等表象,通过地应力测试分析,判断隧道穿越地段围岩属中等应力水平,预测洞室开挖过程中有发生弱岩爆甚至中等岩爆的可能,采取加强监控、优化支护参数及施工工艺和打设应力释放孔等措施,取得显著效果。

High crustal stress being a common geological disaster in tunnels,the accurate mastery of the engineering geological conditions and the state of the crustal stress of the section through which the tunnel is going before the starting of its construction is of vital importance.With the superficial phenomena of the sounding of the surrounding rock of the caves and the cracks in the shotcrete of the initial support behind the work face of the Houyuntai Mountain Tunnel taken into account,it is found that,through the analysis and measurement of the crustal stress of the section,the surrounding rock of the tunnel belongs to the medium stress level,thus predicting the possible emergence of weak or even medium rock burst in the process of the excavation operation.Upon the basis of the geological prediction,technical measures of strengthening geological monitoring,optimizing support parameters and construction processes,digging stress-releasing holes,etc.are taken,thus obtaining remarkable results.