Citation

Stratfull RF. Transp. Res. Rec. 1974; 500: 1-15.

Copyright

(Copyright © 1974, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

An electrically conductive asphalt concrete was made by substituting coke breeze for the natural aggregate. Paving a bridge deck with the electrically conductive asphalt concrete indicated that cathodic protection could be applied to the reinforcing steel. The cathodic protection was measured to be effective when the corrosion of steel strips embedded in concrete containing 10 percent calcium chloride by weight of the cement was stopped. It is estimated that, for the approximately 3.300 sq ft (307.6 sq m) of bridge deck under cathodic protection, the top mat of reinforcing steel has an applied current density of 0.7 mA/sq ft (7.5 mA/Sq m) of steel surface. The total current used is about 1.0 A with a driving voltage of 1.65 V for a total power requirement of 1.65 W. As an experimental method of repair, 2 polymers and an epoxy were injected to bond the undersurface fractures. The epoxy could be injected in all cases where the concrete emitted a hollow sound when struck with a hammer. However, the epoxy could not be injected when the concrete emitted a hollow sound from only the use of the chain drag but not from the use of the hammer. The cost of the cathodic protection installation is estimated to by about 3 dollars/sq ft of deck (33 dollars/sq m).