CHLORIDES IN BRIDGE DECK DETERIORATION

AS A RESULT OF A RECENT BRIDGE DECK STUDY AND OTHER RELATED WORK, A MATHEMATICAL EXPRESSION WAS DERIVED WHICH DESCRIBES THE DISTRIBUTION OF CHLORIDE IN CONCRETE AS RELATED TO DEPTH BELOW THE SURFACE IN BRIDGE DECK CONCRETE. THE VALIDITY OF THE EXPRESSION IS SUPPORTED BY A SIMILAR DISTRIBUTION OF SALT FOUND IN PILES SUBMERGED IN BAY WATER. DATA ARE GIVEN WHICH SHOW THAT THE DISTRIBUTION OF CHLORIDE IN CONCRETE IS HIGHLY VARIABLE, AND ATTENTION MUST BE GIVEN TO THE NUMBER OF SAMPLES WHEN DETERMINING THE AVERAGE CHLORIDE CONTENT. STEEL WAS REMOVED FROM ONE BRIDGE DECK AND CORROSION LOSS MEASURED. WHILE NOT STRUCTURALLY SIGNIFICANT, THE CORROSION THAT HAD OCCURRED WAS MORE THAN NECESSARY TO CAUSE EXTENSIVE CRACKING OF THE CONCRETE. IT WAS CONCLUDED THAT DECK DETERIORATION DUE TO CORROSION OF THE STEEL COULD BE EFFECTIVELY PREVENTED IN NEW STRUCTURES BY THE USE OF A NONCORROSIVE DEICING AGENT, OR THE USE OF AN EFFECTIVE SEALING MEMBRANE TO PREVENT SALT INTRUSION. A MEMBRANE PLACED ON A HIGH CHOLRIDE CONTAMINATED DECK IS LIKELY TO ACCELERATE CORROSION. HALF-CELL POTENTIAL MEASUREMENTS WERE MADE ON SECTIONS OF TWO BRIDGE DECKS. THEY SHOW THAT CORROSION ACTIVITY OF THE STEEL CAN BE NON- DESTRUCTIVELY DETECTED BY ELECTRICAL MEASUREMENTS. /BPR/

  • Corporate Authors:

    California Division of Highways

    Bridge Department
    Sacramento, CA  USA  05914

    Bureau of Public Roads /US

    400 7th Street, SW
    Washington, DC  USA  20590
  • Authors:
    • Spellman, D L
    • Stratfull, R F
  • Publication Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 00212068
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Report/Paper Numbers: D-3-11
  • Files: TRIS
  • Created Date: Apr 20 1970 12:00AM