Effects of Binary and Ternary Blended Cements Made from Palm Oil Fuel Ash and Rice Husk Ash on Alkali–Silica Reaction of Mortar

摘要

Alkali-silica reaction (ASR) of binary and ternary blended cement mortars made from fine particles of palm oil fuel ash (PA) and rice husk ash (RA) was investigated. Portland cement type I was replaced by PA, RA, and RA mixed with PA at rates of 10, 20, 30, and 40% by weight of binder and was used for casting mortar to investigate compressive strength and expansion due to ASR. After finishing ASR test, microstructures of the mortars due to ASR were also investigated by scanning electron microscope and energy-dispersive X-ray spectrometer. The results showed that PA and RA are good pozzolans considering in terms of compressive strength. For ASR results, the expansions of PA mortars due to ASR were lower than control mortar, while the mortars containing RA had very high expansion and many cracks. However, RA-PA mortars provided lower expansion due to ASR than RA mortars at the same rates.