| Abstract [eng] |
In Lithuania, self-healing concrete additives are increasingly used in the production of concrete and reinforced concrete structures. However, there are no prepared regulatory documents to ensure their effectiveness. This is caused by the low interest of Lithuanian scientists in this direction and the lack of research. This master's final degree project reviews the performance of crystalline admixtures and their effectiveness under natural conditions, and presents the European Cooperation in Science and Technology (COST Association) research on self-healing concrete additives. Reinforced concrete structures are exposed to various environmental factors and chemical elements during their lifetime. These effects have a major impact on the life span of the structures, as they can cause corrosion of both the reinforcement and the concrete itself. Similarly, these factors can negatively or positively influence the performance of concrete admixtures. Concrete and reinforced concrete samples, which were made using crystaline admixtures, are the subject of this project. During the experiments, the effect of chemical solutions on healing of cracks was determined, methods of evaluation of crack healing efficiency were compared, influence of additives in reinforcement corrosion processes, shrinkage deformations were considered. In addition, the depth of carbonation in samples with and without additives is determined. Performed tests can be used to evaluate the crack healing efficiency of self-healing concrete. In addition, considering the environmental conditions under which the structures will be used, it can be determined whether it is rational to use crystalline additives to increase the durability of the structures, since under certain conditions the performance of these additives is reduced. |
