The report deals with mathematical models for concrete at early age. In the hardening process chemical reactions take place and the concrete skeleton is created. The processes changes the moisture content and produces heat. The associated temperature rise gives expansion of the material which may lead to cracks in the later cooling phase. The matrial model has intrigate couplings between the involved mechanics, and in the thesis special emphasize is put on the creep behaviour. The mathematical models are based on experimental analysis and numerical implementation of the models in a finite element concept.