ABSTRACT
In the construction of underground openings by the conventional tunnelling, the stability of tunnel face cannot be ensured depending on rock mass conditions, and collapse phenomenon that threatens the safety of workers may occur. For this reason, many studies have been carried out about the stability of tunnel face. However, most of previous studies have been performed without considering the spatial heterogeneity of geomechanical properties. In this study, in order to grasp the effect of spatial heterogeneity of geomechanical properties on the stability of tunnel face, basic stability analyses of tunnel face considering the spatial heterogeneity of geomechanical properties in soft rock mass were carried out based on the random field theory. As a result, it was clear that the effect on maximum shear strain around tunnel face became large depending on heterogeneous condition and ratio of strength of rock and overburden pressure in soft rock mass.
