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D. Suza, J. Kollegger, H. Müller, R. Breiner:
"Comparison of creep and shrinkage of large concrete specimens with theoretical models";
Talk: fib congress 2018 - better, smarter, stronger, Melbourne, Australia; 2018-10-07 - 2018-10-11; in: "Better, Smarter, Stronger", (2018), ISBN: 978-1-877040-14-6; 414 - 415.

In order to design sustainable and economically valuable engineering and architectural structures out of reinforced or prestressed concrete it is necessary to create realistic and practical models for the material behaviour. The appropriate modelling of the processes initiated by the discharge of hydration heat, shrinkage and creep, which occurs in young concrete, is crucial for the subsequent durability of engineering structures. The verification of the serviceability limit state is significantly influenced by the detailed description of the material properties during the design stages.

The evaluation of concrete creep and shrinkage effects is usually done in the laboratory with cylinder with 150 mm diameter and 300 mm height. These specimens are small in comparison to real structures. For the observation of the real concrete rheological behaviour, large concrete specimens with cross-sections up to 1 m² were produced, which have similar dimensions as concrete elements at a construction site.

For the observation of the concrete creep effects, the specimens were loaded with prestressing bars causing a compressive stress of 10 MPa. The test parameters are specimen size, concrete compressive strength and ambient condition (summer/winter). The concrete strain monitoring on the large-scale specimens is performed continuously. Conventional laboratory tests take place simultaneously to validate and compare the measured data. In the paper the experimental results will be compared to the creep and shrinkage models contained in the Eurocode.