"Glascrete" - Concrete with glass aggregate

Post-consumer glass represents a major component of solid waste, yet its us e as an aggregate in concrete is problematic because of the strong alkali-s ilica reaction (ASR) between the cement paste and the glass aggregate In a research project at Columbia University the use of crushed waste glass as a ggregate for concrete products was investigated. Fundamental aspects of ASR in concrete with glass aggregate were studied. it was shown that waste gla ss ground to U.S. standard sieve size No. 50 or smaller causes mortar bar e xpansions in the ASTM C 1260 test of less than 0.1% which is less than that of reference bars without any glass. Also, green glass does not cause any expansion to speak of and finely ground green glass has the potential of an inexpensive ASR suppressant. Specific concrete products with glass aggrega te are currently under development. These include concrete masonry blocks w ith 10% mixed-color waste glass aggregate and "glascrete" Products with 100 % color-sorted glass aggregate for numerous architectural and decorative ap plications.