Abstract
The use of calcium nitrite es a corrosion-inhibiting admixture in reinforced concrete hes been studied on two bridges· the Kentucky 152 Bridge in Washington County and the Gose Road Bridge in Boyle County. Calcium nitrite was added to concrete used in the slabs, diaphragms and barriers of the KY 152 bridge and only in the slab of the Good Road bridge.
Construction of both structures was monitored in the fall of 1986. Placement of concrete on both bridges was satisfactory; however, problems were experienced in finishing the concrete. The finishing problems were related to: 1) concrete 'stickiness', 2) use of spinning-drum screed, 3) use of tyning for deck grooving and, 4) contractor inexperience with the concrete. The finishing problems included; 1) pulled or exposed aggregate, 2) pull cracks, 3) unclosed surface voids and 4) irregular grooves.
Compressive strength of the calcium-nitrite admixed concrete for both bridges exceeded 6,000 psi at 28 days. Freeze-thaw tests of specimens from the Gose Road bridge concrete (that incorporated a super water reducer) indicated no deterioration at 360 freeze-thaw cycles.
Half-cell, corrosion-potential tests were conducted on both bridge decks in March 1987. Those tests revealed no active corrosion in either bridge. In July 1987, corrosion-potential and polarization-resistance tests were performed using stainless-steel reference electrodes buried in concrete across the deck of the Gose Road bridge. Those tests revealed that reinforcing steel in the bridge was in a passive state and that no active corrosion was occurring.
Recommendations are included on remedying concrete-finishing problems. It is recommended that other experimental bridges be constructed using calcium nitrite.
Report Date
9-1988
Report Number
KTC-88-2
Digital Object Identifier
http://dx.doi.org/10.13023/KTC.RR.1988.02-2
Repository Citation
Hopwood, Theodore II; Hunsucker, David Q.; and Courtney, Edgar E., "Calcium Nitrite as a Corrosion Inhibitor in Reinforced Concrete Bridge Decks" (1988). Kentucky Transportation Center Research Report. 515.
https://uknowledge.uky.edu/ktc_researchreports/515
Notes
The contents of this report reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein. The contents do no necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names and trade names are for identification purposes and are not to be considered as endorsements.