ABSTRACT
Creep and shrinkage are essential characteristics of the material behaviour of concrete. To study the influence of real environmental conditions on the time-dependent material behaviour, back in 2017, a long-term testing campaign on large-scale specimens was initiated by the Research Unit Structural Concrete at TU Wien, and the measurements are still ongoing. The long-term testing campaign consists of 12 large-scale specimens, which are stored outside and they are exposed to real environmental conditions. The measurements of more than eight years indicate the influence of environmental conditions on the time-dependent behaviour. Furthermore, a pronounced influence of the production date (the season of the year in which the concrete elements are cast) is observed. A theory capable of implementing the influence of the changing environmental boundary conditions is needed to capture this influence in the model. The extended micro-prestress solidification theory (XMPS) provides an appropriate framework for capturing this influence. Therefore, the paper presents a four-step approach to model the influence of environmental boundary conditions on the temperature, moisture and hydration field. To clarify the question posed in the title, the measurements of more than eight years are compared with the prediction of the model using the measured environmental boundary conditions. The comparison shows, that the measured behaviour of the concrete specimen is replicable with the model if the environmental boundary conditions are appropriately implemented. Furthermore, the influence of the coupling between the hydration field, temperature field and moisture field is studied, and the comparison with the measured data shows that the full coupling between these fields leads to the best model prediction.
