ASTM C1693-11 (R2017) PDF Download

ASTM C1693-11 (R2017) is a standard specification that covers the autoclaved aerated concrete (AAC) product. This product is a cementitious material made up of calcium silicate hydrates with low density achieved through the inclusion of an agent that creates voids. The curing process for AAC involves high-pressure steam.

The standard specifies the raw materials used in the production of AAC, which include portland cement or blended cements, quartz sand, water, lime, gypsum or anhydrite, and an agent for creating voids. The quartz sand can be replaced with a siliceous fine aggregate, and it is usually ground into a fine powder before use. Fly ash can also be used as a replacement for sand.

The manufacturing process begins by thoroughly mixing the batched raw materials to form a slurry, which is then cast into steel molds. Chemical reactions occur within the slurry, causing it to expand in volume. After setting but before hardening, the material is machine cut into various sizes. These units are then steam-cured under pressure in autoclaves, resulting in the formation of a hard calcium silicate product.