Investigation of the Effect of Different Bacteria Species on the Self-Healing of Cement Composites


Erbakan M. (Executive), Şahin Y.

Project Supported by Higher Education Institutions, 2020 - 2023

  • Project Type: Project Supported by Higher Education Institutions
  • Begin Date: April 2020
  • End Date: September 2023

Project Abstract

Cementitious composites such as concrete, mortar and pulp are the most used building materials on earth due to their relatively low costs and strong structural properties. 7 to 8% of the carbon dioxide that is released into the atmosphere by industrial processes is due to cement production. Therefore, it is important to extend the life of cementitious composites. Cracks occur under various loads and loading conditions in concrete and reinforced concrete structures. Substances such as water, chloride and acid that ingress through these cracks cause decreased the lifespan of the concrete and corrosion in the steel reinforcement. Due to these cracks, high cost of maintenance and repairs of reinforced concrete structures are required. Although some chemical-based crack repair materials are available, considering their damage to the environment, environmentally friendly and sustainable repair materials are needed. Biomineralization is the process of formation of water-insoluble aggregates formed as a result of metabolic activities of various microorganisms. In recent years, calcium precipitation processes of microbial origin have been used in repairing cracks in reinforced concrete structures. In this way, it is aimed to increase the compression strength of the cementitious composite and prevent the corrosive agents from being absorbed through cracks. In the proposed study, mortar samples prepared by Marinobacter sp and Halomonas sp, which are bacteria species that have not been used in self-healing studies, will be examined in terms of self-healing properties. Alternatively, bacterial mixtures will be applied on crack-induced concrete surfaces and closure of the cracks will be monitored. Concrete samples will be cured at different temperatures and in different environmental environments such as sea water and then subjected to mechanical and physical tests. In this way, it is aimed to develop a system with the potential to heal spontaneously in reinforced concrete structures which are built in corrosive environments such as sea water.