关键词: 掘进巷道, 临空巷道, 顶板破碎, 支护工艺优化

Abstract: To reduce the surrounding rock fragmentation during the upward excavation of the 8304 high-level gas drainage roadway in Xiaotashan Coal Mine when it passes to the overlying No.4 coal seam goaf，the mechanism of surrounding rock fragmentation is analyzed from aspects of construction technolo⁃ gy，coal seam occurrence，roadway layout，and goaf. For the overlying softened rock mass in the cross-lay⁃ er section，cross-layer grouting solidification is adopted. For the broken coal mass in the roof，shallow hole grouting reinforcement is used to improve the strength of the bearing layer of the soft rock roof. Rib�penetrating cable anchors are utilized for advanced control of the easily collapsing coal pillars on both sides，and combined active and passive support such as "interlocked trapezoidal sheds + dense U29 steel sheds" is employed to strengthen the roof support. Field application effects show that after the implementa⁃ tion of the combined support，phenomena like roof cracking and subsidence caused by the softening of overlying rock layers due to water seepage are effectively controlled. The measured coal seam subsidence after support is reduced to 0.17 m，the support failure rate is lowered to 4%，the roadway repair cost is de⁃ creased to 127 000 yuan，and the excavation speed is increased to 4.8 m/d，which solves technical problems such as high support difficulty，poor effect，and severe surrounding rock deformation in roadways excavated adjacent to goafs，achievines significant application results.

Key words: excavation roadway, gob-side roadway, broken roof, optimization of supporting technolo? gy