TY  - JOUR
T1  - Reduction of Alkali-Silica Reaction Expansion using Ultrafine Palm Oil Fuel Ash
AU - Asrah, Hidayati AU - Karim Mirasa, Abdul AU - Bolong, Nurmin AU - Abdul Mannan, Md AU - Madi, Muhammad 
JO  - Journal of Engineering and Applied Sciences
VL  - 12
IS  - 19
SP  - 4820
EP  - 4825
PY  - 2017
DA  - 2001/08/19
SN  - 1816-949x
DO  - jeasci.2017.4820.4825
UR  - https://makhillpublications.co/view-article.php?doi=jeasci.2017.4820.4825
KW  - Alkali-silica reaction
KW  -ultrafine palm oil fuel ash
KW  -mortar expansion
KW  -ementitious material
KW  -extra calcium silica hydrate
KW  -TGA
AB  - This study presents the effect of Ultrafine Palm Oil Fuel Ash (UPOFA) in controlling the Alkali-Silica
Reaction (ASR) expansion in mortar bar through pozzolanic reactivity, alkali binding, reduction of aggregate
dissolution and change in the Alkali Silica Gel (ASG) composition. The expansion of mortar bar was
investigated using the Accelerated Mortar Bar (AMBT) by replacing 10-40% of cement with UPOFA. The
effects of how UPOFA reduced the ASR were then studied by conducting the pozzolanic activity test, Thermo
Gravimetric Analysis (TGA), aggregate dissolution and Scanning Electron Microscopy (SEM). It was found
that 20-40% UPOFA has the ability to reduce the ASR expansion in a mortar. The higher the amount of
replacement, the lower the ASR expansion recorded. Strength activity index at 7 and 28 days showed higher
pozzolanic reactivity indicating the formation of Extra Calcium Silica Hydrate (CSH) through pozzolanic reaction
and this was supported by the TGA analysis of the CSH and Calcium Hydroxide (CH) content. The aggregate
dissolution was reduced with an increment of POFA replacement level. The change in the chemical composition
of the ASG indicates the transformation of the ASG characteristic from hard to soft and less vicious gel which
explains the lower ASR expansion when ultrafine UPOFA was used as supplementary cementitious material in
mortar bar.
ER  -