Strength, Durability, and Thermal Properties of Glass Aggregate Mortars

Abstract

This study investigated the use of glass aggregates as a building and construction material through the assessment of strength, durability, and thermal properties of cement mortars. A combination of crushed glass and glass beads was incorporated in the mortar specimens as 30%, 50%, 70%, and 100% replacement of natural sand. Compressive strength was studied, until 365 days, using standard (20°C) and accelerated (50°C) curing conditions. A decrease in strength was observed with increasing glass aggregate amount. Nonetheless, higher strength gain was evident in glass aggregate mortars cured in standard conditions at later ages. Qualitative analysis of durability by means of plastic shrinkage cracking indicated that full replacement of natural sand with glass aggregates reduces 96% of cracks as compared to mortar containing no glass. Further, chloride permeation of glass aggregate mortars was improved with increasing glass replacement and age due to the inherently impermeable nature of glass particles. Glass aggregates also improved the overall thermal conductivity of mortar because glass itself has low thermal conductivity.