The influence of deicing salt exposure on the gas transport in cementitious materials

• Gas transport properties were measured for concrete previously exposed to deicing salts.
• Gas transport decreases in presence of deicing salts.
• Salts precipitation in the pores during drying appears to have small impact on transport.
• The degree of saturation increases in concrete exposed to deicing salts.
• The increase of the DOS is estimated to be the main reason of reduced gas transport.

The gas transport properties of concrete can provide useful information for the prediction of the service life. However, to interpret the transport properties properly, some corrections may be needed to account for the moisture content and the distribution of moisture in the concrete. This paper investigates the influence of deicing salts on gas transport. Specifically, oxygen permeability and oxygen diffusion were examined for mortar samples initially saturated with different deicing salt solutions and then exposed to drying. The presence of deicing was found to increase the degree of saturation of mortar samples and as such it decreases permeability and diffusivity. These findings were further confirmed through desorption analysis. This study suggests that care must be taken when performing investigations on concrete previously exposed to deicing salts either in situ or when this concrete is extracted and used for laboratory testing.

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