| A serious form of deterioration is that which is caused
by corrosion of embedded reinforcing steel. This deterioration is initiated by
deicing salts, used for snow and ice control in the winter months, penetrating
the concrete. As the reinforcing steel corrodes, it expands and creates a crack
or subsurface fracture plane in the concrete at or just above the level of the
reinforcement. The fracture plane, or delamination, may be localized or may
extend over a substantial area, especially if the concrete cover to the
reinforcement is small. It is not uncommon for more than one delamination to
occur on different planes between the concrete surface and the reinforcing
steel. Delaminations are not visible on the concrete surface, however, if
repairs are not made, the delaminations progress to open spalls, and with
continued corrosion, eventually affect the structural integrity of the deck. |