Roughness Evaluation for Distinguishing Fresh and Sheared Rock Joint Surfaces with Different Sampling Intervals

The subtle alteration of surface geometry from a fresh to sheared usually results in considerable variation the shear strength jointed rock mass. Through profiling surfaces granite joints before and after tests, an evaluation scheme was newly proposed by determining desirable characteristic index sampling interval measurement order distinguish joint quantitatively. measured data demonstrated that although mean Z2 (root-mean square first derivation) values all profile lines were confirmed reasonable for estimating roughness coefficient (JRC) value surface, it could not completely evaluate surfaces. Meanwhile, distribution slope angles, as parameter, proved enable clearly incorporating small scales (?0.1 mm). numerical simulations implemented mechanical model confirm critical effect slight change further prove 0.1 mm sufficiently capture evolved waviness unevenness Overall, our study provide new clues evaluating can be beneficial understanding during process.