Use of waste glass as fine aggregate in ambient cured alkali‐activated mortars

Abstract

AbstractThis study investigated the feasibility of using two types of waste glass sand as fine aggregate replacement in ambient cured alkali‐activated mortars (AAMs). Fly ash (FA) and ground granulated blast furnace slag were used as aluminosilicate source materials to produce the AAMs. The waste glass sand was used to replace 0%, 25%, 50%, 75%, and 100% fine aggregate (by mass) in AAMs. The influences of the use of waste glass sand, for the replacement of fine aggregate, on slump flow, setting time, compressive strength, and flexural strength of ambient cured AAMs were evaluated. It was found that the slump flow and setting time of ambient cured AAMs significantly increased as the percentage of replacement of fine aggregate by waste glass sand increased. However, the compressive and flexural strengths of ambient cured AAMs decreased when 50% and over fine aggregate were replaced by waste glass sand. The ambient cured AAMs with 25% replacement of fine aggregate with waste glass sand achieved the highest compressive and flexural strengths. Scanning electron microscope analysis indicated that the increase in the compressive strength and flexural strength of AAMs was due to the bridging‐like effect and filling effect provided by the waste glass sand. The use of waste glass sand as a partial replacement of fine aggregate in ambient cured AAMs was found to be feasible. In addition, 25% of the fine aggregate replaced by waste glass sand resulted in the best mechanical properties for ambient cured AAMs.