Enhancing Concrete Durability and Sustainability: Exploring the Potential of Metakaolin for Self-Healing Concrete

Abstract

Sustainable development of the construction industry requires the utilization of various new compounds. However, environmental concerns regarding harm from raw material exploitation, carbon emission, and demolishing activities associated with structure failure due to loads, serviceability, environmental exposure, and repair or maintenance have brought pressure to redesign traditional concrete. Numerous studies focus on using supplementary cementation material as a partial substitute for cement. Additionally, the self-healing technology of the concrete focusing on automatic repair features, when subjected to damage, is also developing a new trend. Metakolin, a calcined clay – Kolin, is a supplementary cementitious material used as an admixture to produce cement replacement. Open microcracks in concrete can be repaired by CaCO₃ precipitation attributable to a revolutionary method called bacterial self-healing. Hence, an attempt has been made in the present study to utilize both the pozzolanic material and developing self-healing features in the same concrete. Initially, the mix was used to find the optimum dosage of metakaolin and self-healing compound dosage individually in the concrete matrix. Later, their optimum dosages were utilized in designing Hybrid concrete. As worked out at the individual substitutions, optimum values of metakaolin replacement and self-healing compound had positive results; similarly, introducing the optimum percentage of both materials yielded fruitful results compared to traditional concrete. This investigation has shown that the metakaolin substitution and introduction of a self-healing compound in the mix can produce high-performance and smart concrete.