Etude expérimentale de l'interaction endommagement-température-état de contrainte-perméabilité du béton

ABSTRACT The objective of this study is to investigate damage-temperature-permeability interactions in structural concrete. The tests are performed on hollow cylindrical concrete specimens, subjected to compressive loading and temperature up to 150°C. The results emphasize that at stress levels lower than 80–85% of the peak stress, the variation of permeability is small and it is slightly influenced by the stress. As the load exceeds 80–85% of the peak stress and approaches the peak, microcracking increases rapidly, causing an important increase of the permeability. In the post-peak phase the increase of permeability is much larger due to significant macrocrack width growth. The increase of permeability with the applied mechanical load seems to be greater with temperature, inducing the further alteration of concrete and dilation of the porous structure of the material. Finally, the obtained results reveal that the effects of damage and temperature may be decoupled for the estimation of the concrete permeability.