加旦—良马引水隧洞超前支护方案设计与施工

Scheme Design and Construction of Advanced Support in Jiadan-Liangma Diversion Tunnel

对加旦—良马引水隧洞在地质条件差、围岩覆盖厚度小、施工环境复杂情况下的超前支护方案进行分析,主要采用的超前支护手段有大管棚、小导管、锚喷等,配合钢拱架、排水等措施,并对施工设计思路、施工方法、超前地质预报、现场监控量测等内容进行了介绍。实践证明,所采用的超前支护方案对防止围岩恶化、控制隧道变形作用很明显。

The advanced support methods in Jiadan-Liangma diversion tunnel were analyzed in the cases of poor geological condition,thin cover thickness of surrounding rock and complex construction environment.The methods of advanced support mainly included large pipe shed,small pipe and blot-shotcrete working with measures like steel arch and drainage.The design idea,construction technology,advanced geology forecast and on-site monitor measurement were introduced respectively.Practices show that the advanced support methods have obvious effects on preventing surrounding rock from getting worse and on controlling tunnel deformation.