Effects of compressive strength and young modulus of gypsum-ceramic waste on autoclaved aerated concrete (GCW-AAC) Available to Purchase

Gypsum and ceramic waste are two types of municipal solid waste (MSW) which usually has been sent for disposal in landfills and become an environmental problem and contribution to green house gas (GHG) emissions. The production of gypsum and ceramic waste in Malaysia has been increasing each year due to the growth development. Today, the Malaysian government is committed to reducing the MSW sent to landfills to 40% and minimizing GHG emissions intensity by 45% by 2030. To reduce the negative effect of gypsum and ceramic waste on the environment, gypsum and ceramic waste (GCW) have been used as an alternative natural source for partial fine aggregate replacement on autoclaved aerated concrete (AAC). The AAC with different composition of GCW (5%, 10%, 15%, 20%, 25% and 30% wt) has been prepared. The compressive strength and Young’s modulus of fresh AAC have been tested according to ASTM D695. The results showed a better performance in compressive strength when fine aggregate was replaced by 5% to 20% of GCW. The compressive strength of AAC increased with GCW ratio from 6.293 MPa (GCW = 5% wt) to 7.904 MPa (GCW = 20% wt) or from 23.3 to 55.5%. The maximum value of compressive strength was 7.904 MPa for 20% wt of GCW. Furthermore, for a partial sand replacement material, the compressive strength decreased when the GCW ratio increased to 25% and 30% replacement. But the compressive strength of AAC with 25% of GCW was still higher than the control sample around 32.3%. Meanwhile, Young’s modulus showed a linear correlation with compressive strength and increased with increasing compressive strength. Our results indicated the GCW led to enhance compressive strength and Young’s modulus of AAC samples but not more than 25% wt. Except for 30% wt of GCW, all AAC-GCW samples havegrade-6 AAC and can be used for wall applications such as partition walls, party walls, basement walls, and shear walls.