The main aim of this study was to investigate the improved autogenous healing of concrete caused by a crystalline admixture in combination with textile reinforced concrete (TRC). This phenomenon (improved healing) has not yet been described by any independent study, and not at all in relation to TRC. The results of the study confirmed that the interaction between TRC and the crystalline admixture’s self-healing ability is advantageous and usable. The application of crystalline admixture could ensure the long-term entirety of the TCR element, where microcracks could occur. This allows for the creation of advantageous, thin (achieved by TRC) and waterproof (achieved by the crystalline admixtures) concrete structures. Moreover, this does not depend on temperature in the range of 4–30 °C (lower temperatures are of course problematic, as for most other cementitious materials). However, the interaction of both materials has its limits; the cracks must not be too wide (max. 0.1 mm), otherwise they will not heal. On the other hand, the advantage is that it does not matter what type of cement is used (CEM I and CEM II showed the same results), and the composition of the newly formed crystals in the cracks corresponds to the composition of the C-S-H gel, so it can be assumed that secondary hydration of the Portland cement occurred in the crack area.

There are usually used inorganic substances for the strengthening of self-healing ability of concrete but some specific types of bacteria or fungi may also be considered for use. The bacteria’s ability to fill pores and micro-cracks was investigated on cylindrical concrete specimens with the diameter 55 mm and height 5 mm. Bacteria Bacillus pseudofirmus and fungus Trichoderma reesei was used for the experiment. The main objective of the experiment was to investigate, if it is possible to use Bacillus pseudofirmus and Trichoderma reesei for self-healing concrete. The results show, that it is more advantageous to use Bacillus pseudofirmus than Trichoderma reesei in alkaline environment. It is desirable to create the most ideal conditions for microorganism’s growth, as possible. Bacteria should have positive effect on self-healing ability of concrete. Any effect of fungus on self-healing ability of concrete wasn’t confirmed.

Ventilated wall is an air-insulating method, which principle is to create a ventilated cavity along the surface of remediated underground wall (usually masonry). The paper describes an innovative solution of this remediation method based on the precast blocks made form textile-reinforced concrete - TRC. The main advantages of the solution (compared to traditional constructions - masonry, hollow bricks filled by cement mortar, monolithic concrete) are low labour difficulty, fast montage and high durability. Since the blocks are not structurally connected or anchored to remediated structure, it is a non-invasive method, which is also suitable for installation in historically valuable buildings. The technical solution is protected by patent CZ307501(B6).

Cracks in the concrete part of substructure are a problem in terms of penetration of water into the building. The best way is to prevent their development or support autogenous healing of concrete as much as possible. It is suitable to create many small specimens for research of crack evolution in various boundary conditions. TRC is applicable material for this research due to its compact dimensions and the ability to create a lot of cracks in relatively small area of the specimen. There are two basic methods how to create cracks in this material, tensile and bending loading. Each method provides different crack shapes.

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