超大断面地下洞室地质灾害分析与防治

Analysis and Prevention of Geological Disasters in Underground Caverns with Super Large Section

大岗山水电站泄洪洞开挖断面大,地质条件复杂,发生地质灾害的几率较高。以此为依托,对超大断面地下洞室地质灾害的划分进行总结归纳。通过对工程地质条件的分析,得出地下洞室地质灾害的影响因素,包括隔水层岩层岩性及其组合特征、含水条件、水头压力及地应力等。最后,分别就软岩洞段和特殊洞段围岩地质风险和断层破碎带、岩脉突泥涌水风险部位提出防治措施,取得大型地下工程灾害防治技术相关经验。

The flood-discharge tunnel of Dagangshan Hydropower Station has a large excavation section and complex geological conditions, so the probability of geological disasters is high. Based on this engineering, the division of geological hazards in super-large section underground caverns was summarized. Through the analysis of engineering geological conditions, the influencing factors of geological disasters in underground caverns were obtained, including the lithology of the aquifer rock and its combination characteristics, water-bearing conditions, head pressure and ground stress. Finally, the prevention and control measures were proposed for the surrounding rock geological risks of soft rock tunnel section and special tunnel section, and burst mud and gushing water locations of fault fracture zone and rock dyke, respectively. The relevant experience in disaster prevention technology for large-scale underground engineering is obtained.