Preparation and characterization of super low density foamed concrete from Portland cement and admixtures

摘要

Foamed concrete with its super low density of between 150 kg/m~3 and 300 kg/m~3 was prepared by means of chemically foaming and so called mixing and foaming process in laboratory. Conventional Portland cement was selected as the main binding material instead of rapid hardening special cement such as sulfoaluminate cement. Chemical and physical admixtures were properly introduced for the regulation of the Theological property and hardening speed of the fresh cement mixture slurry as well as the physical properties of the hardened foamed concrete. The resultant foamed concrete with its curing age of 28 d thus obtained presents its compressive strength between 0.33 MPa and 1.1 MPa, water absorption between 6.6% and 8.3% and thermal conductivity between 0.05 W/mK and 0.07 W/mK.