Results of destructive mechanical characterization and microstructural evolution of samples after exposure to LOCA ambient conditions: ACES Deliverable 4,4

The VeRCoRs concrete has been exposed to LOCA (Loss Of Coolant Accident) conditions of temperature (150°C), relative humidity (90%), and absolute pressure (0.52 MPa) during 14 days and then cooled. Post-LOCA mechanical properties were investigated and compared to that of the unaffected samples. Unconfined compression tests provided compressive strength and Young’s modulus, splitting tests provided tensile strength while and three-point bending experiments conducted on prismatic notched samples provided fracture energy. Aside from following the samples from a mechanical perspective, detailed mineralogical and microstructural characterization was also carried out to study the effect of LOCA conditions. Mineralogical characterization was performed by combining information from X-ray diffraction, thermogravimetric analysis and Fourier transform infrared measurements, while microstructural characterization was performed by combining water porosity, scanning electron microscopy and optical microscopy measurements.