The construction industry faces a pressing need for the development of sustainable materials to mitigate its environmental impact. Today, twice as much concrete is used than all other building materials combined in construction. Portland cement, the main ingredient in concrete production is one of the most energy intensive materials produced, after aluminium and steel, with approximately one tonne of CO2 emitted per tonne of cement produced. Utilising supplementary cementitious materials (SCMs) as a partial clinker replacement is one of the most effective ways to reduce cement’s carbon footprint. Algae is a natural and abundant resource that sequesters carbon during its growth and requires minimal processing to be powdered. Existing studies show raw marine brown algae, when added as a dry substitute, has no negative effects on cement and shows that the various strength properties of concrete increased with the addition of the marine algae. This research investigated algae infused concrete, from production to use, powdered marine brown algae was added at 10% and 15% replacements and found the introduction of algae prolonged the setting time of cement, a 10% algae replacement takes three times as long to set when compared to that of original Portland cement (OPC). Contrary to existing journals and their methodologies, when methodologies were replicated; Findings so far show that algae in its raw form would work to reduce carbon, with a 18% CO2 reduction for the 10% replacement, but it would not work as an industry SCM due to its higher cost, slower curing time, and low compression strength.
Moore et al. (Wed,) studied this question.