Rock masses comprise systems of discontinuities developed by tectonic action or diagenesis, and occasionally imposed by excavation, which bound blocks of intact rock. Fluid flow is determined by distribution of the discontinuities and by the way in which their apertures respond to natural and imposed stress fields in the rock masses. This book develops simple usable fracture flow models based on an understanding of discontinuity structures and on the mechanics of rock and discontinuity deformation, incorporating these into simple models derived from percolation theory. Using these models, the reader is able to analyze and predict fluid flow through rock for hydrological problems and also for the design of underground structures where inflow is a problem.
