Sulphate Resistance of Aerated Concrete Containing Palm OiludFuel Ash as Partial Sand Replacement

摘要

This research investigated sulphate resistance of aerated concrete containing palm oil fuel ash asudpartial sand replacement. Plain aerated concrete with 100% river sand was used as control specimen. Aeratedudconcrete containing palm oil fuel ash was prepared by integrating 30% of the ground palm oil fuel ash as partialudsand replacement. For strength determination, both mixes which cast in form of cubes were subjected to waterudcuring up to 90 days. The compressive strength test was carried out in accordance to BS EN 12390-3 at 7, 28udand 90 days. The sulphate resistance of concretes was investigated by measuring the length change of mortarudbars which immersed in 10% Sodium sulphate solution after water cured for 28 days. The measurement of lengthudchange was taken on weekly basis following the procedure outlined in ASTM C1012-13. Aerated concreteudcontaining palm oil fuel ash exhibits continuous strength development as curing age become longer. Integrationudof palm oil fuel ash makes the concrete microstructure to be denser through formation of secondary C-S-H gel.udThe pozzolanic reaction also reduces amount of calcium hydroxide that can react with sulphate ion to formudgypsum and ettringite which cause concrete deterioration. It is concluded that using ground palm oil fuel ash asudpartial sand replacement assist aerated concrete to exhibit higher compressive strength and better durability toudsulphate attack. ud