  We investigate the bulk rheology of dense granular flow down a rough slope,
where the density profile has been found to show a plateau except for the
boundary layers in simulations [Silbert {\it et al.}, Phys. Rev. E {\bf 64},
051302 (2001)]. It is demonstrated that both the Bagnold scaling and the
framework of kinetic theory are applicable in the bulk, which allows us to
extract the constitutive relations from simulation data. The detailed
comparison of our data with the kinetic theory shows quantitative agreement for
the normal and shear stresses, but there exists slight discrepancy in the
energy dissipation, which causes rather large disagreement in the kinetic
theory analysis of the flow.
