AN ESTIMATION ON THE EFFECTIVENESS OF GROUND SUPPORT ON SHORTSPAN ADVANCING DRIFT AS AN AUXILIARY CONSTRUCTION METHOD IN SQUEEZING ROCK

Abstract

Generally, the bench cut excavation is adopted in squeezing rock. However, advancing drift is used as auxiliary method for the occurrence of large-scale earth pressure in Nikkureyama Tunnel II. This paper studies field measurement data of, Nikkureyama tunnel II. It examines the effect of bench cut and advancing drift by using 3D-FDM. Also, it proposes optimum drift length and bench length from the above result.