Investigation of crack development in a fairfaced concrete floor

The present work shows the crack behaviour of fairfaced concrete floors and the accurate prediction of cracking. The causes for cracking are various and can be divided into cracking of an early stage concrete and cracking of concrete of a later stage. Here the cracking of the concrete at an early stage due to shrinkage taking into account the strength evolution during hardening, will be analysed. Shrinkage causes a reduction of the structures’ volume, it tries to constringe. If the boundary conditions are inconvenient, it may cause cracks. Besides, there are thermal causes based on hydration. As a consequence thereof, the strength of concrete develops in the first days after pouring, too. When the concrete starts to cool down, strains may occur which leads to cracking. For that reason, an experimental investigative program is achieved. With the use of a large climate chamber, in which temperature and humidity can be varied, special specimen with a large surface to volume ratio is stored. An available prognosis software program will give the resulting strengths and internal temperatures at different locations and different instants of time of the investigated elements. These results will be implemented into the finite element models