Effect of chemical composition of different types of recycled glass used as aggregates on the ASR performance of cement mortars

Glass with different chemical compositions, deriving from separate collection, has been used as fine aggregate to formulate cementitious mortars, substituting natural sand. Glass coming from cathode-ray tube monitors, fluorescent lamps, and crystal glass (from production of home décor items) along with glass deriving from soda-lime glass containers, which has been taken as a reference, have been investigated. Glass solubility has been determined in alkaline environment similar to the one inside the cementitious composites. Alkali silica reaction has been tested on glass modified cement mortar in different accelerated conditions. The obtained results highlight an expansion behaviour of mortar samples containing glass with chemical composition different with respect to soda-lime glass. This behaviour is largely dependent on the ratio among modifier and stabilizer oxides in the glass and affects its solubility and consequently the gels composition when alkali silica reactions take place.