Permeability and Seepage Flow - Rock Mechanics Based on an Anisotropic Jointed Rock Model - page 145

which is frequently encountered in nature (Figs. 2.18, 2.36 and 2.37). In Fig. 6.13 the
orientations of the discontinuity sets coincide with the coordinate axes. If the orienta-
tions of the discontinuity sets do not coincide with the coordinate axes the permeability
tensor for each discontinuity set must first be computed in accordance with (6.34) and
then superimposed. In the example illustrated in Fig 6.14, a pronounced anisotropy of
permeability results, although relatively small differences between the mean apertures
of the individual discontinuity sets were adopted.
Figure 6.13 Equivalent permeability tensor of a rock mass with an orthogonal discontinuity system,
orientations coinciding with the coordinate axes