Abstract:

When TBM boring in the unfavorable geology at the exit section of Gaoligongshan Tunnel, some incidents such as soft rock convergenceinduced TBM jamming, broken rock collapse, rockburstinduced spalling, high temperature damage and mud and water gushing happen, which indicates bad TBM adaptability. Therefore, some key technical solutions, i.e. variable section and lift type excavation technology, water body and rock mass integration advance prediction technology, concealed and normalized advanced drilling technology, frontmounted and automated concrete jet technology, enhanced and largescale primary support technology, forced cooling ventilation system, cutterhead and cutter optimization design technology, and rapid material transportation technology, are proposed and applied. And then, a domestic TBM with the maximum diameter of 9.03 m is jointly developed and tested in site. According to the problems encountered in site test, some TBM technical solutions are optimized and improved, and the application effect show that the drill footage per month reached more than 400 m in the early application stage.

Key words: Gaoligongshan Tunnel, complex geology, TBM development, TBM application, TBM adaptability