Study on properties of cement composite with partial substitution of bottom ash as cement

Abstract

The bottom ash is generated from the bottom of the incinerator and commonly known as trash consists of common items we used in daily life, Municipal Solid Waste (MSW). The sample of bottom ash has been taken from XCN Technology Sdn. Bhd. incinerator plant at Pangkor Island. Several test has been conducted such as X-Ray Fluorescence (XRF), particle size analysis, slump test, compressive test, flexural test and water absorption to compare the standard concrete with concrete substutition of bottom ash concrete. The objective of this research were to identify properties of properties of cement composite with partial substitution of bottom ash as cement. Using bottom ash in the concrete, it can help to reduce the high environmental impact of concrete industries and to the rising demand of infrastructure. Through this research, the concrete had replaced the quantity of cement with the bottom ash in 0%, 5%, 10% and 15% ratio. From this research, based on XRF result prove that bottom ash has a same major composition element with cement contains of Fe, Mg, Ca, Al, K, Si, Cl and Na. Compression strength of cube concrete containing with 5%, 10% and 15% of bottom ash is still acceptable for most structural applications based on the compressive strength results since the highest replacement of bottom ash strength observed where 27.74 MPa, 24.44 MPa and 23.80 MPa is more than 20 MPa on 28 days curing for 1:2:4 concrete grade. The best result of water absorption rate is when the value of water absorb is not more than 10% and all of sample had achieved. The flexural strength values of 5% is 1.44 MPa and 10% 1.33 MPa of bottom ash substitution prism increased considerably comparable to the strength of the reference prism at the age of 7 days which is 1.23 MPa and the flexural strength at 28 days of curing 0.85 MPa which is not reach the reference prism strength bending at the age of 7 days. As a conclusion, the substitution of cement with bottom ash can reduce the cement content and economical saving.