The effect of external load on the chloride migration resistance and the service life of reinforced concrete structures and repair mortars

The existing models for the service life design of concrete structures exposed to chloride lack the possibilities to consider the effect of accelerated aging due to load-induced microcracks, since the respective formation of the cracks (widths, length, shape) cannot be summarised in generally valid factors. Thus we propose an approach related to the level of the applied load and not to the properties of appearing cracks to consider this effect. We therefore designed a set-up to determine the impact of external loading on the non-steady-state chloride migration coefficient Dnssm of various concrete and mortar mixes. We were able to point out a correlation between the applied load level and increasing Dnssm-values and a influence of the aggregate size on the intensity of this effect. A final comparative study directly quantifies the impact of load-related increasing migration coefficients on the service life of concrete and mortar components.