Geotechnical problems encountered by tunnel boring machines mining in sedimentary rocks

摘要

Under favorable sedimentary rock mass conditions, the Tunnel Boring Machine (TBM) can excavate tunnel at rates unrivalled by other mining methods. However, the TBM's performance can be severely compromised by a wide range of adverse conditions encountered underground. In such conditions the TBM can become a liability. This paper notes the excellent performance achieved by open TBMs in favorable rock mass conditions and describes how recurring geotechnical problems have negatively impacted TBM performance in other case histories. The impacts of these geotechnical problems and the various mitigation measures that have been taken to counter such impacts are reviewed and a recommendation made to encourage increased systematic reference to case history data sets during the planning and design of TBM tunnels in sedimentary rocks.