Utilization of Solid Wastes (waste Glass and Rubber Particles) as Aggregates in Concrete

Post-consumer glass represents a major component of solid waste. On the other hand, more than 100 million tons of coal combustion ash are generated in the U.S. annually, of which 60 million tons are fly ash. To deal with these problems, two new materials were developed: “glascrete” and “ashcrete.” They have the potential of being made almost entirely from recycled materials: crushed mix-color waste glass as aggregate and activated fly ash (or portland cement) as cementitious binder. The combination of waste glass with portland cement or with activated fly ash offers an economically viable technology for high-value utilization of the industrial wastes. Disposal of waste tires is another serious environmental problem in the U.S. Two innovative materials were developed for utilization of rubber particles in concrete: rubber modified concrete (RMC) and sulfur rubber concrete (SRC). In RMC, the strength loss of the concrete is minimized, and the toughness of the concrete is enhanced by surface treatment of the rubber particles using coupling agents. In SRC, waste rubber particles are mixed in sulfur concrete, and the partial vulcanization process between the rubber and hot sulfur improves the strength of SRC.