A multiphase thermo-hydro-mechanical model for concrete at high temperatures - finite element implementation and validation under LOCA load

International audienceThe aim of this paper is to study the thermo-hydraulic behavior of concrete subjected to severe loading conditions, such as thosetypical of nuclear waste storage structures and PWR-s (Pressurized Water Reactors) vessels in accidental conditions. The paper presentsa coupled Thermo-Hydro-Mechanical (THM) model for the description of concrete at high temperatures. The model is characterized by thepresence of a deformable solid matrix (linearly elastic) filled with three fluid phases (liquid water, vapor water and dry air) and has been implemented in a finite element code (CAST3M) developed by the French research center for nuclear energy (CEA). The code has been validated by means of some simplified tests and has been finally applied for the prediction of the thermo-hydraulic conditions in a concrete slab submitted to a LOCA (Loss-of-Coolant Accident) load