Interaction between damage, temperature, load level and permeability in structural concrete

Author(s): M. Choinska, A. Khelidj, F. Dufour, G. Pijaudier-Cabot
Paper category: Workshop
Book title: International RILEM Workshop on Performance Based Evaluation and Indicators for Concrete Durability
Editor(s): V. Baroghel-Bouny, C. Andrade, R. Torrent, K. Scrivener
ISBN: 978-2-912143-95-2
Pages: 75 - 82
Total Pages: 8
Language: English

Abstract: 
Evolution of concrete transport properties have to be regarded as a function of material and structure degradation, when subjected to set of external loadings. Permeability, considered for certain structures as a direct durability indicator, is particularly sensible to porosity and pores connectivity change, occuring, for instance, due to load or temperature induced cracking. Furthermore, load level may influence concrete permeability.
The objective of presented experimental study is then to investigate damage-temperature-load level-permeability interaction in structural concrete. For this purpose, an experimental device, which allows to measure gas permeability during mechanical and thermal loading, has been developed. The tests are performed on hollow cyclindrical concrete specimens, subjected to compressive loading (in the pre-peak and post-peak phase) and temperature up to 150°C. At stress levels lower than 80% of the peak stress, the permeability variation is insignificant but, as the load exceeds 80% of the peak stress and approaches the peak, cracks tend to localize and damage increases rapidly, causing an irreversible change in the permeability (up to one order of magnitude) due to significant crack width growth. The increase of permeability with loading seems to be greater with the increase of temperature, inducing the alterations of concrete porous material.

Online publication: 2007
Publication Type: full_text
Public price (Euros): 0.00