Excavation analysis of a large-scale underground power house cavern by micromechanics-based continuum model of jointed rock mass

Abstract The governing mechanism of behaviors of rock mass during excavation of a large scale is found to be sliding and opening of joints initially closed by earth pressure. A constitutive model of jointed rock mass is proposed applying MBC (micromechanics-based continuum) approach. The model reflects the behaviors of joints in the analysis of a large-scale cavern. The problem of excavation of a large-scale underground power station cavern constructed by Tokyo Electricity Power Company in Japan is analyzed, and numerical results are compared with measurement data.