APPLICATION OF BIOCHAR AS A SUPPLEMENTARY AND REPLACEMENT ADMIXTURE FOR FERROCEMENT ROOFING TILES

Abstract

Carbon emission reduction is the key agenda on Singapore’s fight against climate change. The increased burning of fossil fuels and deforestation has raised the concentration of CO? on Earth which contributes to global warming. Cement production contributes to about 5-8% of the world’s CO? emissions. Although Singapore has taken several steps to reduce carbon emissions, more innovative and creative sustainable solutions are required to reduce CO? and the utilisation of raw materials. In 1998, HDB in Singapore introduced the application of Ferrocement Roofing Tiles (FRT) to provide additional thermal insulation to its public housings. Over the years, biochar was experimented as a construction material to be an admixture to cementitious mortar. The use of biochar is an effective way to manage waste disposal and reduce CO? emissions from cementitious products. Hence in this research, the application of biochar was used as a supplementary and partial cement replacement admixture for FRT. It was observed from the study that the 4 types of biochar-containing mortar mix (ICS, SDS, LSD and GGBC) had a significant increase in improved average 28th day compressive strength of 23.5%, 27.44%, 38.25% and 22.22% respectively compared to Control. However, the application of biochar in FRT does not provide significantly higher water absorption rate than Control. This could be attributed to the sample and particle size of the specimens. Both tests were substantiated with a series of characterisation tests on the powdered biochar-containing mortar samples. Furthermore, relevant tests were conducted on the biochar containing FRT and ash samples as required by HDB and NEA.