深部巷道过断层破碎带往往应力集中、围岩变形大，是掘进、支护的重大安全隐患。为提高围岩的抗变形能力和强度，减轻巷道锚固支护压力，以淮北矿区巷道过大断层为例，分析了掘进支护过程中矿压大、围岩稳定性差、支护难度大的主要工程问题，采用地面定向孔超前预注浆改性巷道围岩后，顺利掘进通过了断层破碎带。总结提出了基于钻探施工关键技术和高压预注浆关键技术的定向孔掩护巷道过断层关键技术体系，应用四开成孔结构避免了非治理段注浆干扰以及四段注浆分段法实现了断层破碎带精准注浆，并从压水试验、岩性探查、注浆量、注浆扩散距离、物探验证以及掘进支护效果分析方面评价了注浆加固效果。工程实践表明：地面定向孔具有长距离探查巷道岩性、超前高压预注浆的显著优势，改善了软弱围岩力学性质，有效控制了巷道围岩变形，巷道最大底鼓量降比超过62.6%，为巷道支护提供了安全保障，具有重要的推广应用价值。

Stress concentration and large deformation of the surrounding rock are often encountered in the deep roadway passing through the fault fracture zone, which is a major safety hazard for excavation and support. In order to improve the deformation resistance and strength of surrounding rock and reduce the anchoring support pressure of the roadway, taking the large fault of the roadway in the Huaibei mining area as an example, the main reasons for the large mining pressure, the poor surrounding rock stability and the difficulty of supporting in the process of excavation and support were analyzed. After using the ground directional holes to advance pre-grouting to modify the surrounding rock of the roadway, the roadway was successfully excavated and passed through the fault fracture zone. The key technical system of directional hole shielding roadway crossing faults based on the key technology of drilling construction and the key technology of high pressure pre-grouting was summarized and proposed. The fault fracture zone was grouted accurately, and the grouting reinforcement effect was evaluated from the aspects of water pressure test, lithology exploration, grouting amount, grouting diffusion distance, geophysical verification and tunneling support effect analysis.

The application results show that surface directional drilling method has remarkable advantages on exploring rock lithology with long distance and pre-grouting with high pressure. The method improves the strength of the soft and weak surrounding rock and decreases rock deformation, The maximum floor heave of roadway decreased by more than 62.6%. It provides safety guarantee for roadway support. Thus, we believe that the method has generalizable value.