Technical lessons learnt from the case history of tunnel collapses

터널 붕괴사례로 부터의 기술적 교훈

In this study, a database composed by 46 cases of tunnel collapses has been built up. Based on the database, comprehensive data analysis is carried out, providing us a number of the technical lessons, which can be considered in future design and construction to minimize possibility of tunnel collapse disaster. For making a better understanding, the technical lessons are given in two divisions: mountain tunnel and urban tunnel. Tunnel collapses taking place in the former tunnel are generally due to bad discontinuity condition of jointed rock mass. Otherwise, urban tunnel has weak condition generally on ground water and weathering of ground. Most of technical comments given in this paper are made based on the cases of tunnel collapses only used in this study, so that the comments seems to be hard to be available to all the tunnelling cases. However, the comment should be valuable technical lessons for tunnel engineers to consider in tunnel design or construction.