Surface resistivity profiles on marine substructures to assess concrete permeability
ABSTRACT: Surface resistivity profiles (using a wenner probe) as a function of elevation are being measured on young and mature marine reinforced concrete substructures at and above mean water line on bridges at coastal locations in Florida. The surface resistivity values measured are correlated with chloride diffusion coefficients measured from the same structures. Additionally the wet resistivity values from cored specimens are also correlated to the chloride diffusivity. Previous lab work suggests that a good correlation exists on saturated concrete between these two parameters. The objective of this study is to assess whether a similar correlation can be obtained from field surface resistivity readings, such that surface resistivity could potentially be used as performance based monitoring of new and older structures. Preliminary results suggest that a conditioning method needs to be applied on-site to approximate water saturation conditions at the elevations of interest.