Lysinibacillus sphaericus as a self-healing agent for cement-based materials: a preliminary investigation
International Journal of Development Research
Lysinibacillus sphaericus as a self-healing agent for cement-based materials: a preliminary investigation
Received 27th November, 2020 Received in revised form 14th December, 2020 Accepted 15th January, 2021 Published online 24th February, 2021
Copyright © 2021, Marcondes, Carlos Gustavo Nastari et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Self-healing in cement-based materials occurs in order to plug microcracks that can cause harmful agents to enter the material. In this context, the objective of this work is to study the microorganism Lysinibacillus sphaericus and submit it to tests that prove its application in concrete structures to act as a healing agent. For this, it was exposed to growth in a culture medium with different pH alkalis. Then, the concentration of microorganisms in the culture medium was verified by the Petri dish counting method. After this step, the microorganism underwent a 14-day growth in a liquid culture medium rich in calcium to verify its capacity to precipitate calcium carbonate minerals. Investigations of precipitated minerals were conducted by XRD and SEM. The bacterium Lysinibacillus sphaericus precipitated the calcium calcium carbonate and showed growth in the culture medium with alkaline pH. This result is a strong indication that the microorganism is suitable to be applied as a healing agent in cement-based materials.
