Influence of local rice husks ash on compressive strength of normal-strength concrete

It is well known that rice husks ash can be used as cementitous material. However, different climate and geographical conditions could provide different quality of the ash. Therefore, this study aimed to investigate the effect of different percentage of rice husk ash (RHA) taken from Oesao village in Nusa Tenggara Timur-Indonesia on compressive strength of normal-strength concrete. Eight specimens with diameter of 150 mm and height of 300 mm made of normal-strength concrete with replacement of.0%, 5.0%, 10%, 15% of Portland cement with RHA were cast, prepared, and tested until failure. It is found that the maximum strength was observed on specimen with replacement of 10% of the ash.