Strength enhancement and self-healing mechanisms in m45 high-strength concrete incorporating bacillus subtilis: an experimental laboratory study.
DOI:
https://doi.org/10.51168/w9gv2670Keywords:
Bacillus subtilis, Bacterial concrete, M45 concrete, Self-healing concrete, Microbiologically Induced Calcite Precipitation, Mechanical propertiesAbstract
Background:
High-strength concrete (M45) is widely used in structural applications but remains susceptible to microcracking, affecting durability and service life. Bacterial self-healing using Bacillus subtilis offers a potential solution through microbiologically induced calcium carbonate precipitation.
Methods:
An experimental laboratory study was conducted using M45 concrete with and without bacterial incorporation. Encapsulated Bacillus subtilis with calcium lactate was added to the test group. Compressive, flexural, and split tensile strengths were evaluated at 7, 21, and 28 days. Statistical analysis using one-way ANOVA was performed.
Results:
Bacterial concrete demonstrated higher strength across all parameters. At 28 days, compressive strength increased from 47.6 MPa to 53.5 MPa (12.4%), flexural strength from 7.2 MPa to 8.1 MPa (12.5%), and split tensile strength from 4.1 MPa to 4.6 MPa (12.2%). All differences were statistically significant (p < 0.05).
Conclusion:
Incorporation of Bacillus subtilis significantly improved the mechanical properties of M45 concrete through calcite precipitation and matrix densification.
Recommendation:
Further studies are required to evaluate long-term durability, field performance, and cost optimization for large-scale applications.
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Copyright (c) 2026 Hari Kannan Moorthy, Valarmathi Matheswaran, T. Senthil Kumar M.E Thanapal (Author)
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