A comparative study of modeling fractured rock mass around tunnel subjected to excavation load

Fractured rock mass is a complexity of skeleton, pores, and cracks / fractures. The cracks / fractures are distributed in different scales from some millimeters to some kilometers. Modeling this material is still challenge in rock mechanics nowadays. There are some methods in literature to model fractured rock mass such as (1) homogenization technique for all fractures or (2) homogenization technique for a part of fractures combined with explicitly model of remained fractures. More precise in this paper, the fractured rock mass will be considered as two scales: the fractures with scale of some millimeters are accounted by Eshelby’s analytical solution at meso scale while the fractures with scale of some meters will be assembled to model explicitly at macro scale. The effect of explicitly fracture model is highlighted and discussed in this paper through tunnel excavation problem by different finite element case studies.