Fracture Toughness Effects in Geomaterial Solid Particle Erosion

摘要

Effects of fracture toughness on the impingement of geomaterials (rocks and cementitious composites) by quartz particles at velocities between 40 and 140 m/s are investigated experimentally and analytically. If schist is excluded, relative erosion (in g/g) reduces according to a reverse power function if fracture toughness increases. The power exponent depends on impingement velocity, and it varies between -0.64 and -1.33. Lateral cracking erosion models, developed for brittle materials, deliver too high values for relative material erosion. This discrepancy is partly attributed to stress rate effects. Effects of R-curve behavior seem to be marginal. An integral approach E-R = K-1 . E-R(P) + (1 - K-1) . E-R(L) is introduced, which considers erosion due to plastic deformation and lateral cracking. A transition function K-1 = f(K-Ic(12/4) / sigma(23/4)(C) is suggested in order to classify geomaterials according to their response against solid particle impingement.