锦屏辅助洞(西端)岩爆分析及其防治措施

Rockburst Analysis and Prevention Measures at Jinping Auxiliary Tunnels(Western Side)

锦屏辅助洞作为锦屏水电枢纽工程（一、二级水电站）的前期控制性工程，既是沟通东、西雅砻江交通的重要通道，又是锦屏二级水电站引水隧洞的施工辅助洞和地质探洞。辅助洞具有埋深大，地应力高，围岩完整性好、强度高等特点，具备了发生弱-强岩爆的条件。施工过程中高频率岩爆严重困扰着施工安全。在总结锦屏辅助洞岩爆规律的基础上，分析了影响岩爆特征的主要因素，并针对岩爆烈度分级探讨了岩爆综合防治措施，该综合防治措施在实际应用中取得了很好的效果，为接下来的引水隧洞施工积累了丰富经验，并为国内外同类工程提供借鉴。

The construction of the Jinping Auxiliary Tunnels is such a project that governs greatly the progress of the Jinping Hydropower Project （Ⅰ,Ⅱ grade ）. It is a traffic tunnel connecting east and west YaLong Rivers, and more importantly a construction auxiliary tunnel and geological detection tunnel for the diversion tunnels of Jinping Grade Ⅱ Hydropower Station. Jinping Auxiliary Tunnels have the condition of rockbursts occurrence, due to the deep overburden, high in situ stress and intact rock with high strength, and become one of the major difficulties in the construction. Based on the summary of occurred rockburst patterns, this paper analyzed major influential factors of rockbursts, and investigated corresponding integrated prevention measures for various rockburst grade. It is demonstrated from the actual utilization that the measures are very effective to reduce the roekburst occurrences and grade. This study accumulated a wealth of experiences for the construction of diversion tunnels in the next phase, and also provided a meaningful reference to similar projects in the future in China and other countries.