CONSTITUTIVE RELATIONS OF UNSATURATED SEEPAGE FLOW IN FRACTURED ROCK MASSES
裂隙岩体非饱和渗流本构关系

Based on the numerical simulation of two dimensional unsaturated flow in a single fracture with the continuum approach,an evaluation on the application of Van Genuchten(VG) model and Brooks-Corey(BC) model in fractured rock mass is presented and an improved constitutive relation model is obtained by mainly comparing VG and BC models with the simulated and measured results. Although VG model can reasonably well match the simulated water retention curves,both VG and BC models underestimate relative permeability. Simulation results indicate that an improved model,derived from combination of Brooks-Corey relative permeability-saturation relation and the VG capillary pressure-saturation relation,can generally describe the characteristics of unsaturated flow in fractured rock masses,but the effectiveness of the model in some aspects needs further research,such as the relation curves for higher saturation condition.