Corrosion Propagation in Cracked and Uncracked Prestressed Piles.

This paper presents results from a comprehensive, cradle-to-grave study in which electrochemical measurements (corrosion potential and corrosion rate), crack progression, and gravimetric metal loss were recorded for one-third-scale Class V prestressed specimens exposed for over 3 years to a simulated outdoor marine environment. These data were used to isolate the effect of cracking on the corrosion rate and determine the appropriate oxygen permeation coefficient values that were used to quantify the differences in corrosion propagation between the cracked and uncracked states. The permeation coefficient in cracked sections was found to be more than 20 times larger than that in uncracked ones. It was also higher than that for reinforced concrete specimens under comparable wetting-and-drying saltwater exposure. The findings predict that comparable (Class V) full-size prestressed pile specimens will crack within 3 years of the destruction of the passive layer (depassivation). [ABSTRACT FROM AUTHOR]