Determination of rheological phenomenon is very difficult, because there are many unknown inputs parameters, e.g. concrete age, the size of elements, relative humidity of the surrounding environment, cement hydration rate, temperature influence, type of strain and treatment.
This Ph.D. thesis deals with the effective cross-section thickness and its effect on the behaviour of concrete constructions that is how the rheological phenomena change in time as a result of the application or removal of insulation layer from the concrete surface. Long-term experimental measurements of specimens and real bridge constructions were performed. The data collected from these measurements were described, evaluated and mathematical modifications for the standards Model Code 2010 and Model B4 (B3) have been proposed. Using these new computational formulas is possible to take into consideration the changes in the effective cross-section thickness and therefore make the computational models for concrete structures more accurate.