The research project shall provide answers to the questions:
- influence of climatic conditions such as temperature, humidity exposure on the electrical resistivity of cement based materials and on the corrosion rate for different concrete qualities,
- relation between concrete resistivity and corrosion rate and the limiting conditions,
- resistivity measurements for the prediction of the future corrosion behaviour.
Based on a laboratory study the research project shall establish quantitatively the influence of humidity and temperature as well as pore structure on the electrical resistivity of cement based materials.
In a second phase the influence of temperature on the (macro cell) corrosion of steel in concrete shall be investigated.
Were successfully investigated following aspects on the concrete resistance:
- humidity and
- concrete quality.
The connection to the corrosion rate was found clearly only for dry concretes.
Only dry concrete is susceptible to climatic conditions influencing its resistance in above threshold limits.