The paper deals with the experimental determination of shrinkage development during concrete ageing. Three concrete mixtures\nwere made.They differed in the amount of cement in the fresh mixture, 300, 350, and 400 kg/m3. In order to determine the influence\nof plasticiser on the progress of volume changes, another three concrete mixtures were prepared with plasticiser in the amount of\n0.25% by cement mass. Measurements were performed with the goal of observing the influence of cement and plasticiser content\non the overall development of volume changes in the concrete. Changes in length and mass losses of the concrete during ageing\nwere measured simultaneously. The continuous measurement of concrete mass losses caused by drying of the specimen�s surface\nproved useful during the interpretation of results obtained from the concrete shrinkage measurement. During the first 24 hours of\nageing, all the concrete mixtures exhibited swelling. Its magnitude and progress were influenced by cement, water, and plasticiser\ncontent. However, a loss of mass caused by water evaporation fromthe surface of the specimens was also recorded in this stage. The\nmeasured progress of shrinkage corresponded well to the progress of mass loss.
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