Hydraulic characterisation of some arenaceous rocks of Molise (Southern Italy) through outcropping measurements and Lugeon tests

Lugeon tests have also clearly shown the heterogeneous nature of the sandstones. Discontinuity aperture and rock permeability have been calculated with reference to the theory of Rissler and assuming a simplified hypothesis for relative roughness. These values (mean value of aperture = 0.35 mm; range of values of hydraulic conductivity = 10− 5 − 10− 2 m/s) are comparable to values determined from surface survey (mean value of aperture = 0.39 mm; range of values of hydraulic conductivity = 10− 6 − 10− 2 m/s).The convergent results obtained from the two methods of investigation are indicative of the complementary nature of the two approaches adopted when the hydraulic characterisation regards the portion closest to the surface of the rock mass.