Self-healing ability and waterproofing of cementitious materials with crystalline additive: development and assessment of a permeability monitoring method

Introduction. The development of self-healing cementitious composites for cracks represents a promising approach to increasing the durability of reinforced concrete structures and reducing repair costs. Accelerated restoration of water resistance after defects in concrete is important for hydraulic engineering and infrastructure projects.

Aim. The aim of the study was to evaluate the self-healing ability of cementitious materials with a waterproofing additive and to develop and test an effective method for permeability monitoring through artificial defects of controlled size.

Materials and methods. Experiments were conducted in laboratory and field conditions in Portugal and Russia. Permeability was assessed using both rapid methods (visually, by the appearance of bubbles) and specialized equipment (BB-2, installation according to EN 123908, UVF-6). The study compared compositions with and without a waterproofing additive, monitoring defects of 0.3–0.5 mm in width.

Results. The developed method ensures highly accurate self-healing assessment. It has been established that the additive accelerates the restoration of water resistance; the effect is particularly pronounced for cracks of 0.3 and 0.4 mm and with acid treatment of the surface. Under field conditions, a significant reduction in the length of filter cracks and the formation of crystalline deposits confirming chemical self-healing are observed.

Conclusions. The method is practical for assessing the self-healing properties of cementitious materials. The waterproofing additive facilitates complete restoration of water resistance even with defects up to 0.5 mm, while maintaining the vapor permeability of the structure. The obtained results can be used to standardize the assessment and improve the maintainability of reinforced concrete structures.

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