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

Autoclaved aerated concrete (AAC) containing ceramic-gypsum waste (CGW) as a partial substitution for sand and pure AAC were fabricated in this study.The compressive strength ranged from 1.64 MPa to 2.13 MPa, and work density ranged from 594 kg/m 3 to 605 kg/m 3 .All AAC samples were exposed to direct fire at 923.8C for 300 seconds.The maximum surface temperature (T1) and opposite surface temperature (T2) were 930.1C and 31.7C,respectively.The average T1 of the sample was around 169.88C, and the average thermal storage was around 10.36% after cooling for 900 seconds.Meanwhile, the average T2 was 31.3C,almost similar to the workshop temperature.Except for pure AAC, the samples did not crack, burn, or melt during exposure to direct fire at a temperature of 920C for 300 seconds.Direct fire testing also positively affected the work density and compressive strength of AAC-CGW.The average work density decreased by 10.69%, and compressive strength increased by 12.39%.The maximum work density was reduced by 14.57 % for AAC-1, and compressive strength increased by 39.15% for pure AAC.This study demonstrated that the AAC-CGW is suitable for thermal and fire resistance walls due to their excellent durability and strength after exposure to direct fire.