This contribution deals with the performance of concrete structures subjected to fire loading. Starting with the experimental investigation on the material scale, the development of material parameters like Young's modulus and Poisson's ratio are determined. A new testing device allows to test specimens under combined mechanical and thermal loading. Furthermore, this test setup allows to monitor the displacements of the specimens with increasing temperature, giving informations about the load induced thermal strains (LITS). The experimental data is finally used for validation of a proposed micromechanical model. Finally, structural simulations are performed using the micromechanical model. Moreover, different material models are used for calculation of different tunnel cross-sections, allowing an assessment of state-of-the-art material models.