宜万铁路齐岳山隧道F11断层由断层角砾岩、破裂岩、断层泥组成，断层内富含高压水，超前探孔单孔最大涌水量1 800 m3/h，水压力2.5 MPa。针对F11高压富水断层，前期按“以堵为主、限量排放”施工原则，采取全断面帷幕注浆措施，注浆工程量大、进度慢。为及早攻克F11高压富水断层，建设单位多次邀请院士、专家现场踏勘、研讨，提出“注浆加固、分水降压、快挖快封、加强监测、综合治理”施工技术方案，将全断面帷幕注浆调整为外堵内固注浆。对于高压富水断层，通常的设计是加固圈厚一些、加固体强一些，而外堵内固注浆是将隧道周边岩体、水量及水压力分布假定为不均匀性，从而通过超前探孔锁定弱水区和强水区，针对弱水区采取基本注浆，对强水区采取加强注浆，注浆机理为“封堵裂隙、减少水量；固结围岩、改良地层。”注浆时，先通过区域定位孔进行无约束注浆堵水，从而使地层中水量得到有效控制，然后按“合理步距、封堵水流，由外到内、环环相扣，间隔跳孔、锁定水源，增加补孔、区域加强”的注浆理念进行注浆施工。通过现场实践，外堵内固注浆能达到注浆堵水和加固效果。外堵内固注浆与全断面帷幕注浆相比，注浆孔数量和注浆量减少50 %，在水量大时，注浆进度提高80 %，一般情况下提高50 %以上，因此，外堵内固注浆具有广阔的推广应用价值。

Qiyue Mountain Tunnel F11 fault on Yichang-Wuanzhou Railway is formed by breccia, broken rocks and fault gouge composition. It is rich in high-pressure water, with the biggest single whole water inflow of 1 800 m3/h and water pressure of 2.5 MPa. In earlier stage, F11 fault followed the principle of "mainly blocking up and limiting discharge"  and grouted the whole cross-section, the construction quantity was huge and the progress was slow. To overcome F11 fault early, the construction technology of "grouting to make solid, using water segrating, excavating and sealing quickly, strengthening monitoring and managing comprehensively"  was proposed and whole cross-section grouting was changed into "outside block and inside strengthen grouting" . The common design for high-pressure water-rich fault is thicker reinforced ring and stronger reinforced body. While "outside block and inside solid grouting"  assumes the distribution of surrounding rock, water quantity and pressures is uneven, then finds out weak water area and strong water area through advanced prospecting holes, and adopts normal grouting for weak water area and strengthened grouting for strong water area, following the principle of "blocking cracks to reduce water quantity, strengthening supporting rock and improving strata" . Firstly, unconstrained grouting is used through area location holes to effectively control water quantity in strata, then grouting is adopted abiding by the principle of "appropriate drawing pace, blocking water flow, from outside to inside, finding water source by interval holes, and adding holes in necessary areas" . Engineering practices show that "outside block and inside solid grouting"  can effectively blocking water and strengthen. The grouting holes and grouting quantity of "outside block and inside solid grouting"  are 50 % less than those of whole cross section grouting, and the grouting speed is 80 % higher when water quantity is large, at least 50 % higher in usual condition.