THREE DIMENSIONAL EFFECTS TO SURROUNDING GROUNDS OF LARGE SECTION TUNNEL BY ADOPTING PILOT TUNNELING

Abstract

Recently, TBM pilot tunneling method has been attracting people's attention to construct a flattered large section tunnel, for instance in the second Tomei-Meishin Highway Project, rapidly, safely and economically. We studied the differences in effect of stress and displacement to the surrounding grounds of the main tunnel due to existence of pilot tunnel, differences in location, strength of support and diameter of the pilot tunnel by three dimendional FEM analysis. And we obtained some utilities of pilot tunneling.