Self-Healing Concrete: Review of Materials and Techniques Used

This report provides a comprehensive review of the current research on self-healing concrete, a promising technology aimed at enhancing the durability and sustainability of concrete structures. The report examines various self-healing mechanisms, including the use of bacteria, microcapsules, and other innovative materials. It explores the performance of these techniques in addressing concrete cracks and improving the overall lifespan of structures. The review covers key aspects such as materials, techniques, and applications, highlighting recent advancements and future directions in this field. Several studies are referenced that showcase diverse approaches to self-healing concrete, including the immobilization of bacteria and the use of calcium nitrate microencapsulation. The report also discusses the practical implementation of these technologies in construction, providing insights into their potential for preventive repair and damage management. Overall, the report offers a detailed overview of the current state of self-healing concrete research and its potential to revolutionize the construction industry.

STRENGTH
Self-Repair- As the name
suggests, this type of concrete
can repair the existing cracks
without any external
maintenance by the labourers.
Longevity- The durability of the
infrastructures, roads and
bridges, if constructed with self-
healing concrete can sustain for
a longer period without any
damage.
Flexibility- Compared to the
normal concrete, the self-
healing concrete is more
compressible and flexible in
nature leading to easy
alignment with the structure.
Reduction in Permeability- Self-
healing concrete incorporates
lesser inter-molecular spaces.
Hence, it does not allow fluids
to flow through it, in turn
increasing the strength of the
infrastructure.
Harmless Bacteria- The self-
healing concrete comprises of
bacteria that is not at all
harmful for human life. Hence,
usage of self-healing concrete
for sustainable construction is
an advantageous factor.
Reduction in Corrosion- The
steel used in the construction is
shielded because the self-
healing concrete has the ability
to protect it from any kind of
corrosion by the corrosive
agents such as acid rain, wind
and so on.
WEAKNESS
Unavailability of Designs- The
designs of the concrete mix and
the nutrients, along with bacteria
in it are not available in IS code or
any other code that proves to be
disadvantageous for the builders.
Expensive- The self-healing
concrete is composed of bacteria
and calcium lactate. The calcium
lactate is made from milk, a high-
cost resource. Hence, the
construction of buildings and
roads using self-healing concrete
leads to huge expense than the
normal concrete ones.
Accurate Percentage of
Ingredients- The strength of the
self-healing concrete is reduced if
the ingredients are not properly
mixed. If the percentage of the
self-healing agents like the calcium
lactate and bacteria increases
more than 20%, the strength of
the concrete reduces.
Requirement of Skilled Labours-
The construction of buildings and
roads with self-healing concrete
requires experienced and skilled
experts who can mix the
ingredients in exact percentages
for construction purposes.
OPPORTUNITY
Future Scope - Due to its
advantageous features, many dealers
in the construction industry, leading
to the industrial growth, incorporate
the self-healing concrete for their
construction purposes.
Concrete Flooring- Self-healing
concrete can find its application in
concrete flooring of the buildings and
incorporate less harmful bacteria
proving to be hygienic for the people
living in it.
Tunnel Lining- The usage of self-
healing concrete in tunnel-lining
helps the tunnel to be non-
permeable and strongly resistant to
natural disasters.
Highway Bridge- In bridges, the self-
healing concrete protects the steel
and other metals from corrosion,
thus increasing the durability of the
infrastructure.
THREAT
Excessive Use of Milk- The milk is an
expensive item required by the
constructors to obtain a proper mixture
of the self-healing concrete. Hence,
excessive use of milk will lead to
decrease in the resource for the people
to consume in the upcoming years.
Poor Mixture of Ingredients- The
labourers might not know about the
mixture ratio and might end up mixing
the self-healing agents more than its
requirement leading to improper
construction projects.
Lack of Awareness- Since not much
people know about its proper usage,
they might not show much interest in
using self-healing concretes than
normal concretes due to its high-cost
measures.
References
Abdullah, M.A.H., Abdullah, N.A.H. and Tompang, M.F.,
2018, October. Development and Performance of Bacterial
Self-healing Concrete-A Review. In IOP Conference Series:
Materials Science and Engineering (Vol. 431, No. 6, p.
062003). IOP Publishing.
Al-Ansari, M., Abu-Taqa, A.G., Hassan, M.M., Senouci, A.
and Milla, J., 2017. Performance of modified self-healing
concrete with calcium nitrate
microencapsulation. Construction and Building
Materials, 149, pp.525-534.
Al-Tabbaa, A., Litina, C., Giannaros, P., Kanellopoulos, A.
and Souza, L., 2019. First UK field application and
performance of microcapsule-based self-healing
concrete. Construction and Building Materials, 208,
pp.669-685.
De Belie, N., Gruyaert, E., Al Tabbaa, A., Antonaci, P.,‐
Baera, C., Bajare, D., Darquennes, A., Davies, R., Ferrara,
L., Jefferson, T. and Litina, C., 2018. A review of self‐
healing concrete for damage management of
structures. Advanced materials interfaces, 5(17),
p.1800074.
Sánchez, M., Al-Tabbaa, A., De Belie, N., Ferrara, L. and
Jefferson, A., 2017. Self-healing approaches for the
preventive repair of concrete structures: SARCOS COST
Action. In 2nd International RILEM/COST Conference on
Early Age Cracking and Serviceability in Cement-based
Materials and Structures (EAC-02) (Vol. 2, pp. 813-818).
RILEM Publications.
Seifan, M., Samani, A.K. and Berenjian, A., 2016.
Bioconcrete: next generation of self-healing
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Xu, J., Wang, X., Zuo, J. and Liu, X., 2018. Self-healing of
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microorganisms. Advances in Materials Science and
Engineering, 2018.
Zhang, J., Liu, Y., Feng, T., Zhou, M., Zhao, L., Zhou, A. and
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