Stochastic two-scale approach on fatigue simulation of concrete specimen

Fatigue tests of concrete specimen in the laboratory typically scatter because of variations on the microscale composition and random micro-crack generation. A computational model for that scenario will be set up in order to understand the mechanism in detail. At the meso-scale a detailed finite element model consisting of cement matrix, aggregates and interface transition zones a model will be studied (typical laboratory specimen). Aggregates and initial defects will be randomly distributed in the model, which is loaded under uniaxial and triaxial conditions. An efficient stochastic collocation scheme will be applied to obtain the homogenized mechanical properties.  On the macroscopic length-scale a homogenized continuum model is assumed where the material properties are described as random-fields based on the statistical information obtained from the meso-model. Again, efficient stochastic schemes will be applied to obtain the statistical information about the damage evolution and fatigue limit. Model parameter will be calibrated to existing lab-experiments which also serve for validation purpose.

Doctoral Researcher: Ammar Airoud Basmaji

Scientific Advisors: Udo Nackenhorst, Frédéric Ragueneau, Amélie Fau