High-strength concretes, compared to normal-strength concretes, generally have a lower water-cement ratio, which means that they contain less water in the mix itself and usually more cement. However, less water and more cement in the concrete mix are the reasons for higher shrinkage, especially during the early curing period of the concrete. Shrinkage of concrete causes tensile stresses which can lead to cracks that impair the durability of concrete elements. In the thesis, in order to reduce the magnitude of shrinkage, 12 % recycled aggregate made from common size bricks was incorporated in the concrete mix in addition to the normal aggregate. The aggregate was pre-soaked in water. As part of the experimental research, measurements of the initial autogenous shrinkage of the high-strength concrete were carried out on sealed test specimens and a compression test on concrete cubes. We found that pre soaked recycled brick aggregate distributed throughout the concrete structure provides internal curing to the high-strength concrete - reducing the early shrinkage of the concrete. At the same time, the compressive strength of the concrete tested was slightly reduced.
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