Der späte Zwang als unterschätzter - aber maßgebender - Lastfall für die Bemessung

The late restraint as an underestimated - but authoritative - load case in design

The design of reinforced concrete slabs for foundation often occurs in the traditional way, i. e. for the load case of effluent hydration heat only. For this purpose the static calculation of the amount of reinforcement needed for the limitation of the crack width bases on assumptions and simplifications which often differ from the actual conditions during the construction process and the service lifeof the structure. One cause that may provoke cracks a long time after finishing the construction is the load case of late restraint. However, it is not the intention of the author to generally propagate the design of reinforced concrete slabs for foundations on basis of this load case. In fact this paper shows a way in order to carry out the static calculations more precisely with regards to the respective characteristic environmental conditions of such structures during their construction process and service life. In the following some comments are given to this topic.