Abstract: A proper spatial effect approach of excavation face is the premise to make full use of the self-bearing capacity of rock mass. In this study, two representative spatial effect approaches of excavation face, i.e., the support stress coefficient approach of T-N (09) and the displacement release coefficient approach of V-D (09), are compared qualitatively and quantitatively about their sources, influencing factors, scopes of application, performances of spatial effect and differences of convergence-confinement and so on. It is found that the two spatial effect approaches of excavation face are both readily combined with ground response curve to practical engineering applications and have good consistency in some range of parameters; the support stress coefficient approach of T-N (09) is only suitable for elastic-perfectly plastic rock, which leads to a smaller support pressure and a larger stable deformation of rock mass, and thus the related material models and parameter ranges should be properly improved. The displacement release coefficient approach of V-D (09) can be applied to various elastoplastic rocks, directly reflecting the changes and influence ranges of spatial effect of excavation face, and thus it has a wide range of engineering applications.

Key words: spatial effect of excavation face, support stress coefficient, displacement release coefficient, support pressure, stable deformation of rock mass