Properties of flowable fill produced by substituting fly ash with recycled glass powder

Abstract

A laboratory study was undertaken to evaluate the feasibility of recycling glass powder (RGP) as a fly ash substitute in flowable fill. A total of ten mortar mixtures and ten flowable fill mixtures were prepared by using different proportions of fly ash (FA), finer RGP (FG) and coarser RGP (CG) powders. The mortar mixtures were tested for determining strength activity index (SAI). The flowable fill mixtures were tested for fresh and hardened properties. Further, microstructural study techniques, namely, scanning electron microscope (SEM) and energy dispersive X-ray spectroscope (EDS), were also used for characterizing the changes in the microstructure of flowable fill due to RGP substitution. It was found that RGP has the potential to be a suitable replacement of FA in flowable fill. However, flow consistency and compressive strength were found to vary with the percent RGP substitution and relative proportion of finer and coarser glass content in the flowable fill mixtures.