Solid-particle erosion of Portland cement and concrete

Solid-particle erosion of Portland cement and Portland-cement-based concret e, and for comparison a nuclear-waste glass, was studied. Using angular Al2 O3 erodents of mean diameter approximate to 42, 63, 143, and 390 mu m impac ting at 20 and 90 degrees to the surface at 50 m/s, we found the erosion ra te to be a strong function of erodent size. Erosion rates of the three targ ets by rounded SiO2 sand erodent of mean diameter approximate to 450 mu m w ere generally different from those for the approximate to 390 mu m Al2O3 er odent. The glass response was characteristic of a classic brittle material; rates were highest at 90 degrees impact. For the cement, degradation due t o local heating and consequent H2O loss may have contributed to material lo ss, and erosion rates were highest at 20 degrees impact. Material loss in c oncrete was caused by a combination of fracture mechanisms. (C) 1999 Publis hed by Elsevier Science S.A. All rights reserved.