Solid-particle erosion of Portland cement and concrete

Solid-particle erosion of Portland cement and Portland-cement-based concrete, and for comparison a nuclear-waste glass, was studied. Using angular Al2O3 erodents of mean diameter approximate to 42, 63, 143, and 390 mu m impacting at 20 and 90 degrees to the surface at 50 m/s, we found the erosion rate to be a strong function of erodent size. Erosion rates of the three targets by rounded SiO2 sand erodent of mean diameter approximate to 450 mu m were generally different from those for the approximate to 390 mu m Al2O3 erodent. The glass response was characteristic of a classic brittle material; rates were highest at 90 degrees impact. For the cement, degradation due to local heating and consequent H2O loss may have contributed to material loss, and erosion rates were highest at 20 degrees impact. Material loss in concrete was caused by a combination of fracture mechanisms. (C) 1999 Published by Elsevier Science S.A. All rights reserved.