Concrete is a widely used construction material with a global production growing by 2.5% annually. However, concrete can easily be cracked and has a limited lifespan. Among strategies for healing cracks and recycling concrete, microbial carbonate precipitation (MICP) by photoautotrophic microalgae showed great potential. Microalgae are considered as a potential crack healing agent due to their biomineralization capacity. The usage of algae as a waste material could have an impact in the consumption of cement. The severity of the greenhouse effect and global warming has been well documented, and the use of alternative cement replacement materials enabled substantial quantity of carbon dioxide reduction. The newly developed algae-based eco-bio concrete (Eco-Biocrete) can absorb carbon dioxide, as well as having the property of excellent heat insulation and heat capacity characteristics.
Microalgae has a great potential to be developed as a medium for concrete restoration through bio-cementation (biological binding). The microalgal biomass was harvested after the culturing in an appropriate media and wastewater, followed by the pilot study of immersing the concrete specimens in the culture media as well as a surficial coat in the form of spray to check the penetration. During the final stage, the physical, mechanical, and microstructural properties of the algae-based mortar or eco-bio concrete (Eco-Biocrete) were evaluated and recorded. The innovative Eco-Biocrete has the potential to heal cracks. The reduction in cost and carbon footprint could be envisaged around 5-15 &10-20%, respectively.
Assoc. Prof. Dr. Ubagaram Johnson Alengaram (PI), Emeritus Prof. Dr. Phang Siew Moi, Prof. Dr. Shaliza binti Ibrahim, Prof. Ir. Dr. Ngoh Gek Cheng, Prof. Ir. Dr. Rozita binti Yusoff, Dr. Vejeysri Vello, Mr. M. Karthick Srinivas. Mr. Ahmed M.E Alnahhal