Effect of Direct Fire Exposure on the Physical and Mechanical Properties of Autoclaved Aerated Concrete (AAC) Based on Ceramic and Gypsum Waste (CGW) as Partial Substitution for Sand

Abstract

Six types of autoclaved aerated concrete (AAC) based on ceramic- gypsum waste (CGW) as partial substitution for sand has been prepared. The compressive strength ranges from 1.64 MPa to 2.13 MPa and work density ranges from 594 kg/m³ to 605 kg/m³. All AAC samples have exposed to direct fire at temperature 923.8 °C for 300 s. The maximum temperatures surface (T₁) and opposite surface (T₂) were 930.1 °C and 31.7 °C respectively. The average T₁ of sample was around of 169.88 °C and average thermal storage around 10.36 % after natural cooling for 900 s. Meanwhile, the average T₂ was around 31.3 °C and almost similar with workshops temperature. Except for pure AAC, the samples were showed not crack, burnt and melt during exposed to direct fire testing at temperature 920 °C for 300 s. The direct fire testing has also positive effect on the work density and compressive strength of AAC-CGW. The average work density decreased by around 10.69 % and compressive strength increased by around 12.39 %. The maximum work density was reduced around 14.57 % for AAC-1 and compressive strength was increased around 39.15 % for pure AAC. This work showed that the AAC-1 to AAC-5 are suitable for wall application such as thermal wall especially for fire resistance wall due to its good durability and strength after exposed to direct fire.