Investigation of Water Destructive Effects on Tunnels

Tunnel excavation disturbed the orientation and intensity of stress field around the tunnel. In addition¡ it becomes drainage systems that change the ground water path and decrease the water level. As a result of this¡ non-uniform pressures distribute on the lining and cause the non-uniform displacement. Water intrusion not only makes trouble in excavation process¡ but also it has many effect on tunnel lining during their working life and on other device like rail¡ electronic and mechanical device and etc. In this paper¡ damaging effects of water on ground (external effect) and tunnel lining (structural effect) was studied. Also¡ its effect during the service time (practical effect) was discussed.