ASTM C1386-07 PDF Download

The ASTM C1386-07 standard is a specification for precast autoclaved aerated concrete (AAC) wall construction units. This standard covers both nonload-bearing and load-bearing wall units made from AAC. AAC is a cementitious product that achieves low density by including an agent that creates voids within the material. These wall units are large rectangular prisms that are laid using a thin-bed mortar. In order to protect the installed units from direct exposure to moisture, they must be coated with a material accepted by the AAC manufacturer.

The raw materials used in the production of AAC include portland cement, quartz sand, water, lime, gypsum or anhydrite, and an agent that creates voids. The sand used as a raw material can be replaced with a siliceous fine aggregate. The batched raw materials are mixed together to form a slurry, which is then cast into steel molds. The volume of the slurry expands due to chemical reactions, and after setting, the mass is machine-cut into various sizes. The units are then steam-cured under pressure in autoclaves to transform the material into a hard calcium silicate.