| Popis: |
Frost damage on the concrete surface might be aggravated when freezing occurs in the presence of a salt solution, like sea water or de-icing salt. A possible mechanism behind this combination of frost and salt is discussed. When freezing takes place in pure water, ice formed at the surface will block inflow of water to the concrete, but it will cause drying of the concrete. When freezing occurs in salt solution, unfrozen water (brine) can enter the concrete surface and make the concrete completely saturated. When pore water freezes, it exerts pressure. The effect of air-entrainment is favourable since it reduces the stresses. A calculation is made of the air requirement for concrete with w/c-ratio 0.45. |
