Self-healing concretes are a special class of concretes that have the ability to self-heal cracks due to the presence of special components in their composition. Their unique feature is that when micro-cracks form in the concrete, a self-repair mechanism is activated - chemical reactions are triggered that gradually close the cracks.
Working Principle of Self-Healing Concretes
The self-healing ability in these concretes is provided by special additives. The most common are mineral additives containing active chemical substances, as well as various fibers and microcapsules with polymers or oligomers. When cracks appear, these substances are released and initiate a curing reaction, which closes the crack with solid material, restoring the integrity of the structure.
Key Advantages of Self-Healing Concretes
The main advantage of these concretes is the increased durability and reliability of concrete and reinforced concrete structures. The self-healing ability reduces the risk of structural failure due to cracking, rebar corrosion, and other damages.
Additionally, the use of self-healing concretes leads to a reduction in maintenance and repair costs for concrete buildings and structures. There is no need for costly and labor-intensive methods of repairing concrete surfaces.
Applications of Self-Healing Concretes
Due to their unique properties, such concretes are widely used in the construction of critical engineering structures - bridges, tunnels, hydroelectric power stations, and nuclear power facilities. They are actively used in the construction of high-rise buildings and industrial structures exposed to aggressive chemical and mechanical influences.
Prospects and Development Directions of Self-Healing Concrete Technology
Currently, active research is being conducted in the field of improving self-healing concretes.
In particular, innovative additives based on nanoparticles of various compounds are being developed, which can accelerate the processes of concrete structuring in the crack formation zone at the molecular level. Complex modifiers with improved catalytic properties for activating crack self-healing reactions are being tested.
Work is also actively underway to integrate sensor systems for monitoring the technical condition of structures into self-healing concretes. This will allow for the prompt detection of damage areas and activation of the self-repair mechanism.
Great attention is paid to increasing the repairability of such concretes by enabling multiple healing of defects under cyclic loads. For this purpose, the composition and structure of the concretes are being optimized, and new types of microcapsules for prolonged release of polymeric binders are being developed.
An important direction is also expanding the operating temperature range and improving the frost and corrosion resistance of self-healing concretes for use in harsh climatic conditions.
Overall, further research is focused on creating high-tech, multifunctional new-generation concretes with a wide range of operational properties.
Conclusion
The technology of self-healing concretes is one of the most promising and rapidly developing directions in modern concrete construction and the construction industry as a whole. The use of such concretes significantly increases the durability and reliability of buildings and engineering structures, as well as reduces the costs of their operation and repair. The implementation of self-healing concretes is an important step towards creating truly "smart" and eco-friendly materials and technologies in the construction industry.