Acidic attack of cement based materials - a review. Part 1. Principle of acidic attack

The growing threat to concrete structures by acidic attack is a worrying topic of increasing significance in over all the world. Therefore, information and data on the principle, rate factors and protection measures against acidic attack of cement based materials are useful. The subjects of Part 1 of this paper are the sources of acidic media and the principle of acidic attack. The aggressivity and effects of inorganic and organic acids, and acidic air pollutants, like carbon, nitrogen and sulfur oxides, are reported. It is shown that the possibility of the acidic attack is conditioned by the universal alkalinity of cement based materials, making them a willing partner in the reaction with acidic species. As shown in Part 2 of this paper, the consequence of this fact is that various types of cement behave in an acid environment more or less as acidic unresistant binders. (C) 2001 Elsevier Science Ltd. All rights reserved.