| Corrosion of steel reinforcement is a major factor in the deterioration of highway bridges. Permeability of concrete plays an important role on the durability of concrete. Concrete, which is impermeable, prevents harmful chemicals, such as sodium and calcium chloride, to come in contact with reinforcement. One can aim to achieve impermeability or reduced permeability through matrix modification.; In this experimental program several concrete mixtures modified with metakaolin (up to 15%) were developed, and tests were performed to assess strength, permeability and corrosion potential of embedded steel reinforcement. Metakaolin improves the water-tightness of cement paste as well as the transition zone.; In order to accelerate corrosion the mixing water in select samples included 5% chloride solution. Specimens were submerged in water as well as 5% chloride solution to further accelerate corrosion of steel reinforcement.; The results indicate that partial replacement of cement with metakaolin improves strength and durability of concrete. |
