以某隧道两处地质条件相近的浅埋富水段为工程背景.针对首次采用管棚穿越时加固及止水效果不佳的问题,研发可回收定位注浆锚管,并应用于第二处浅埋富水段.施工中,通过超前地质预报雷达影像分析加固后岩体破碎程度,以工序时长和开挖难度评价施工难易;结合掌子面围岩固结表象及加固前后BQ值变化,评估破碎围岩固结效果;依据掌子面出水状态和渗水量变化评价止水性能,并通过洞内外位移监测判断围岩整体稳定性.对两处区段的超前地质预报、施工过程、围岩固结、渗水变化及沉降监测结果进行综合对比.结果表明:与管棚加固相比,定位注浆锚管能够显著改善围岩破碎状况,提高围岩等级,降低洞内外位移,缩短变形收敛时间,增强止水能力,并明显加快施工进度.

Taking two shallow-buried, water-rich sections of a tunnel with similar geological conditions as the engineering background, a recyclable positioning grouting anchor pipe was developed and applied to the second section after conventional pipe-shed reinforcement used in the first section proved ineffective in terms of both reinforcement and water sealing. During construction, advanced geological prediction radar images were used to assess the degree of rock-mass fragmentation after reinforcement, while construction difficulty was evaluated based on process duration and excavation conditions. The consolidation effect on fractured surrounding rock was examined through visual observations of the tunnel face and changes in the BQ value before and after reinforcement. Water-sealing performance was evaluated according to the water-outflow condition at the tunnel face and variations in seepage volume, and the overall stability of the surrounding rock was assessed through monitoring of displacements inside and outside the tunnel. A comprehensive comparison was conducted in terms of advanced geological prediction, construction process, rock-mass consolidation, seepage variation, and settlement monitoring. The results show that, compared with pipe-shed reinforcement, the positioning grouting anchor pipe can significantly reduce rock-mass fragmentation, improve the surrounding-rock grade, decrease internal and external tunnel displacements, shorten deformation convergence time, enhance water-sealing performance, and markedly accelerate construction progress.