Abstract
In order to make clear static and dynamic movement of a tunnel face and to assess the stability of the face, three dimensional model experiments of three kinds have been conducted. From the experimental results, it is made clear that excavation prosess of the tunnel face should be taken into account in the experiments to seize the essence of the failure phenomena. Active earth pressure and total force of it measured at the static experiments, which act on the earth retaining structure placed at the tunnel face, show almost the same value calculated by two-dimensional Rankin earth pressure theory. By developing this theory, safety factor equation is proposed for stability assessment of the tunnel face. The results of field measurement at the site support the appropriateness of the safety factor equation proposed.
