This paper aims to evaluate the effectiveness of various curing methods on the properties of hollow concrete bricks incorporating fly ash and bottom ash resulted from coal combustion. Fly ash was used to partially replace the ordinary Portland cement, while bottom ash for the fine aggregates. The composition of the specimens tested was those with optimum composition, i.e. with 30% fly ash, 25% bottom ash, and with filler-to-binder ratio – all by mass - of 8.6. Curing methods evaluated were immersion into water, water spraying with different frequencies, spraying and wrapping with gunny sacks and lastly covering with plastic sheet to prevent excessive evaporation. The properties of hollow concrete bricks elaborated were the compressive strength, water absorption and density. It was found that spraying with water once a day resulted in the highest 28th-day compressive strength of more than 70kg/cm2, which is attributed as Grade I hollow concrete brick in accordance to the relevant Indonesian standard. All of concrete brick specimens showed favorable water absorption properties.
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