Harnessing the Catastrophic Inrush of Water into New Yungchuen Tunnel in Taiwan

摘要

The New Yungchuen Tunnel, a critical part of the Taiwan Eastern Railway Improvement Project, wasrnhit by tremendous inrush of water three years after construction began. The massive water broughtrnabout a huge collapse of the tunnel surrounding rock, and the debris caused by the collapse buried 540rnm of the supported section. Extensive investigations and reinforcements enabled the tunnel to bernbroken through such that the Improvement Project was opened to traffic on time. This paper discussesrnthe countermeasures conducted in the tunnel. The background of the project is briefly described.rnSupplementary investigations and the interpretation of their results are then introduced. A breakingrnthrough philosophy of "draining the far and grouting the near" is developed accordingly.rnCountermeasures and relevant accompanied measures are presented in some detail, and reviewed withrnreference to the results of subsequent monitoring.