Abstract
Palm oil fuel ash (POFA) was utilized as a pozzolanic Material in varied quantities to produce high strength concretes (HSCx) of above 90 MPa, with significant improvement in its engineering and fluid transport properties. The chemical and physical characteristics of ultrafine POFA (U-POFA) utilized in HSCx were investigated along with its concomitant fresh, strength and durability characteristics compared to ordinary Portland cement based type (OPC-HSC). The U-POFA had high surface area of (1.136 m(2)/g-Blaine), mean particle size (2.06 mu m), and glassy phase (70.59%). The HSCx that had replacement level of 0, 20, 40 and 60% of U-POFA recorded the 90-day strength of 100.5, 105.2, 109.0 and 108.5 MPa. Utilizing high volume of POFA in HSCx is possible with improved fineness and heat-treatment at 500 50 degrees C, and could retard water absorption/permeability, setting and chloride penetration/migration rates and achieve better strength. This makes HSCx a better choice in terms of strength and durability for hot weather and underwater concreting, and in corrosive or aggressive environment. (C) 2016 Elsevier Ltd. All rights reserved.