A study of alkali-silica reaction on greenstone aggregate

This research reports on a study to evaluate the effects of greenstone aggregate on alkali-silica reaction (ASR). Greenstone aggregate is developed by University Malaysia Sabah, Malaysia (UMS). It is produced using solid waste materials like Palm Oil Fuel Ash (POFA), waste glass, recycled aggregate and natural fibre. The main purpose of this study is to develop the optimum mix design to reduce the ASR potential of the greenstone aggregate. The reactivity of the greenstone aggregate was determined using Acceleration Mortar Bar Test (AMBT) and Autoclave Test. From the results of these two tests, the greenstone is evaluated as a moderate reactive aggregate with the potential to cause a harmful crack in the concrete. Moreover, the effectiveness of Supplementary Cementing Materials (SCM) – Clay Brick Powder (CBP) was also tested. The expansion of mortars containing 0, 5, 10, 15, 20 and 25% CBP as a partial replacement for Ordinary Portland Cement was studied with autoclaving expansion test and AMBT. Results showed that the amount of CBP required to control the expansion to