为综合治理大区段超高压富水花岗岩蚀变带，通过超前注浆加固降低围岩含水率及增强稳定性，实现TBM脱困复推及导坑恢复开挖，系统性研究极端复杂不良地质下开展超前注浆加固的可行性和关键技术。依托大瑞铁路高黎贡山隧道出口工区实践，建立“地质判识-注浆仿真-工艺革新-材料研发-装备升级”五位一体的技术攻关体系。基于现场地质勘察及蚀变岩特性分析，借助多物理场耦合注浆仿真模拟动水压环境下浆液劈裂裂隙网络的填充形态。提出超前分段注浆可行性升级优化的关键技术要点，并通过现场多次注浆试验，攻关实现3大技术突破： 1）研发大转矩高频次液压回转螺旋钻孔工艺，并以工艺组合的方式攻克地层有效成孔率低的难题； 2）以超细水泥为主体，通过掺入高性能外加剂，创建高渗透、强动水抗分散性的复合型注浆材料； 3）研制超高压钻、注装备配套，构建注浆压力可达15 MPa的超高压系统。将所述超前注浆加固技术应用于工程实践，结果表明： 高性能浆液在动水冲蚀下留存率可达近85%，围岩堵水率达92%～95%，围岩变形量控制在18 mm以内，整体注浆工效提升近72%，已成为现场综合治理超高压富水蚀变带地层的关键技术之一。
Advance grouting reinforcement reduces groundwater inflow and stabilizes surrounding rock, facilitating TBM recovery and bypass tunnel excavation in large-section, high-pressure, water-rich granite alteration zones. The authors systematically investigate the feasibility and key technologies of advance grouting reinforcement under extremely complex and adverse geological conditions. Based on engineering practice at the Gaoligongshan tunnel exit section along the Dali-Ruili railway, a comprehensive technical framework is established—incorporating geological identification, grouting simulation, process innovation, material development, and equipment upgrading. A multi-physical field coupling grouting simulation is conducted to model grout migration within fracture networks under hydrodynamic conditions, leading to the proposal of key technologies for dynamic advance grouting. Field tests yield three major breakthroughs: (1) a high-torque, high-frequency hydraulic rotary drilling system is developed to resolve the low drilling efficiency problem; (2) a high-permeability, dynamic water-resistant composite grout is formulated using ultrafine cement modified with high-performance admixtures; and (3) an ultra-high-pressure drilling and grouting system capable of pressures up to 15 MPa is designed. Engineering results demonstrate that: the system achieves 85% grout retention under hydrodynamic erosion, 92%－95% water-sealing efficiency, deformation control within 18 mm, and an overall grouting efficiency improvement of approximately 72%. This approach proves essential for comprehensive treatment in complex alteration zones.
