Feasibility study on the use of microalgae as an external crack healing agent for cement mortar rehabilitation

• Main Authors: Srinivas, M. Karthick, Alengaram, U. Johnson, Ibrahim, Shaliza, Vello, Vejeysri, Phang, Siew Moi
• Format: Article
• Published: TAYLOR & FRANCIS LTD 2024
• Subjects: TA Engineering (General). Civil engineering (General)
• Online Access: http://eprints.um.edu.my/44326/; https://doi.org/10.1080/21650373.2023.2249889

As conventional concrete repairs have shortcomings and impact the environment, multiple attempts exist to find alternative sustainable measures to address this issue. Microbial-induced carbonate precipitation (MICP) using microalgae is one of the proven methods that can heal microcracks. In this study, the method used in repairing micro-cracks is by spraying microalgae species, namely, Arthrospira platensis and Synechococcus elongatus, cultured in a high calcium-based medium onto the surface of the cement mortar. The crack healing was evaluated for 14 days after the cracks were induced by applying 65-70% of the maximum threshold load. The results show that the microalgal-treated specimens exhibited a higher strength recovery, crack closure, and less water absorption than the control specimen. It is also observed that over 75-80% (0.26 mm, approx.) of the cracks can be healed within the span of 14 days sustainably using microalgae.