FraMCoS 8 2013 Toledo, Spain

Effect of Microcraking on Gas Permeability and Chloride Diffusion of Concrete

Concrete structures near marine environments are subjected to a combination of chloride and varying stress conditions resulting in both macro and microcracking. Knowledge of the transport properties of cracked concrete is essential for predicting its durability. The impact of damage…

First page of: Effect of Microcraking on Gas Permeability and Chloride Diffusion of Concrete
Year 2013
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Abstract

Concrete structures near marine environments are subjected to a combination of chloride and varying stress conditions resulting in both macro and microcracking. Knowledge of the transport properties of cracked concrete is essential for predicting its durability. The impact of damage upon gas permeability and chloride diffusion through ordinary concrete (OC) and high performance concrete (HPC) was carried by an experiment in the present study. Concrete cylinders were induced microcracks by mechanical uniaxial compression between 60% and 90% of the ultimate strength. The damage of specimens was evaluated by elastic stiffness degradation and ultrasound pulse velocity. After unloading intrinsic gas permeability was measured using a constant head permeameter, the chloride migration coefficient was evaluated by migration test in steady state conditions, with the same concrete specimen. The damage of specimens showed correlation with gas permeability and chloride diffusion of concrete in this experiment. A linear correlation was obtained between intrinsic permeability coefficient and chloride diffusion coefficient depending on the damage variable, specific for each concrete type (OC and HPC).