Effect of water content on the compressive strength of biomineralized bricks.

Production of fired clay bricks is extremely energy consuming and emit massive carbon dioxide to the atmosphere. Such a problem caused global warming, rising sea water level, and melting of icebergs. This paper aimed to document the compression behavior of green bricks produced from the cyanobacterial calcium carbonation mechanism that can serve as a sustainable alternative to fired clay bricks. Phytoplankton was collected from a lake in Serdang, Selangor Malaysia. The phytoplankton had a high concentration of cyanobacteria. It was then mixed with a calcium source, China clay, and river sand under the designated mixture proportions with varying water contents for the purpose of casting the green bricks. After the green bricks were subjected to 28-day biomineralization process, they were tested for their compressive strength. The green brick with a water content of 400 mL had the highest compressive strength of 3 MPa. This implied that the degree of water saturation influenced the biomineralization process of the green brick as the water content must be optimized for the maximum calcium carbonate precipitation to occur in it. At an optimal water content of the brick admixture, there was a positive effect of the cyanobacteria from the phytoplankton on the biomineralization of the green bricks. The outcome of the research work contributed to the advanced knowledge of sustainable construction in the brick making industry. [ABSTRACT FROM AUTHOR]