High-Strength Concrete Containing High Volume Ground Palm Oil Fuel Ash

Abstract

This research aims to study compressive strength and total shrinkage of high strength concrete containing high volume ground palm oil fuel ash. Palm oil fuel ash (POFA) was ground by grinding machine until the particles retained on a sieve No. 325 of less than 1% by weight. Then, ordinary Portland cement (OPC) was replaced by ground palm oil fuel ashes at the rates of 60, 70 and 80% by weight of binder. The total binder content of concrete was 560 kg/m³ and water to binder ratio was set as a constant of 0.25. Superplasticizer was used to control the slump of fresh concrete between 150 to 200 mm. Compressive strength of concrete was investigated at 7, 14 and 28 days, and modulus of elasticity of concrete was investigated at 28 days. The total shrinkage of concrete was determined at 1, 3, 7, 14 and 28 days. The results indicated that the use of ground POFA to replace OPC at 70% by weight of binder gave compressive strength at 28 days of 69.2 MPa which was as high as that of CT concrete. The modulus of elasticity of high volume ground POFA concretes was related to its compressive strength, i.e. the modulus of elasticity of concrete was increased with the increased compressive strength of concrete. The total shrinkage of concrete was reduced when the cement replacement level by ground POFA increased.