Examining Concrete Properties Containing Recycled Glass Cullet as a 100% Fine Aggregate Replacement

Open Access
Author:
Wright, Jared Robert
Graduate Program:
Civil Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
May 10, 2012
Committee Members:
  • Farshad Rajabipour, Thesis Advisor
Keywords:
  • Glass
  • concrete
  • glasscrete
  • compressive strength
Abstract:
Over 600,000 tons of glass per year cannot be recycled into new glass. These glasses are subsequently stockpiled or landfilled. A ‘greener’ and more efficient use of this glass cullet is to find use in engineering materials. This thesis investigates the use of glass cullet as a 100% fine aggregate replacement in Portland cement concrete (glasscrete) systems. Washed glass sand was produced in order to achieve a fineness modulus similar to natural sand for use in concrete. After mixture proportioning, the fresh and hardened properties of glasscrete were evaluated and compared to natural sand concrete on a basis of similar compressive strength or similar water-to-cementitious material ratio (w/cm). The objective was to create empirical data that would provide material engineers and suppliers design specifications on the proper methods of proportioning glasscrete mixtures. In order to mitigate the deleterious alkali-silica reaction resulting from the use of silica glass as a fine aggregate, a class F fly ash was used to replace 20% of cement by weight. Fresh property testing showed that glasscrete has better workability than natural sand concrete. Hardened property testing showed that glasscrete needs a lower w/cm to reach similar design strengths. At similar strengths, glasscrete has an earlier initial and final set time, lower coefficient of thermal expansion, greater abrasion resistance, greater resistance to ion penetration, and lower water sorptivity. At similar w/cm, glasscrete has a lower linear coefficient of thermal expansion, greater resistance to chloride ion penetration than natural sand concrete, and a lower water sorptivity than natural sand concrete. However, glascrete is less abrasion resistant at the same w/cm. This study concludes that glasscretes have adequate workability and can sustain loads necessary for field applications. Further research is necessary to examine the glass particle-cement paste interface.