A Study of the Conditions for the Occurrenceof Icicles in Road Tunnel

Abstract: Icicles may growth on the tunnel lining in winter season. Since icicles can cause traffic obstructions and damage to tunnel facilities, tunnel managers prevent icicle-related damages by the patrolling and manually removing works of icicles on the tunnel lining. Therefore, the patrolling and manually removing works of icicles by tunnel managers are very severe works in winter season. In this study, the crack tensor theory is used to evaluate the risk of water leakage in a tunnel. This theory can quantify the permeability based on the geometric relationship of discontinuities on rock mass. In addition, the conditions of the tunnel environment on the day of the icicle occurrence were clarified by analysing the tunnel environment at the time of the icicle growth through actual temperature measurements in the tunnel.