Simulation of Solidification, Relaxation and Long‐Term Behavior of a Borosilicate Glass

High-level radioactive waste (HLW) vitrification is a manufacturing process designed to dispose of nuclear energy fission products over long-term timescales. We studied and modeled the thermomechanical phenomena occurring during the processing of the glass blocks, e.g. during their solidification and their cooling down. The thermomechanical modeling takes place in 3D FEM simulations. The relaxations of the borosilicate glass are to be taken into account through scripted algorithms. They allow us to describe accurately the evolution of the glass properties over its phase transition (the glass transition temperatures are non-uniform in the HLW package). A damage behavior within the frame of Continuum Damage Mechanics is also used to predict the glass cracking surface area.