INVESTIGATION OF MECHANISM OF DELAYED FAILURE OF PRESTRESSING STEEL

THE TENSILE AND APPROXIMATE PLANE-STRAIN FRACTURE TOUGHNESS PROPERTIES WERE DETERMINED FOR ONE LOT OF 1/4-IN. DIA. STEEL PRESTRESSING ROD CONFORMING TO SPECIFICATION ASTM A421. TESTS WERE CONDUCTED IN THE AS-RECEIVED CONDITION AND AFTER TEMPERING AT TEMPERATURES BETWEEN 700 DEGREES AND 900 DEGREES F. CIRCUMFERENTIALLY NOTCHED AND FATIGUE PRECRACKED SAMPLES WERE EXPOSED UNDER A CONSTANT LOAD IN EITHER CEMENT EXTRACT WATER OR DISTILLED WATER CONTAINING SODIUM CHLORIDE AND SODIUM SULFATE TO ESTABLISH THE RELATIONSHIP BETWEEN APPLIED STRESS AND TIME TO FAILURE. THE SAME TYPE OF TESTS WERE REPEATED IN THE DISTILLED WATER SOLUTION WITH THE SPECIMEN EITHER THE ANODE OR CATHODE OF AN ELECTROLYTIC CELL. THESE STUDIES SHOWED THAT PRESTRESSING WIRE IS SUBJECT TO DELAY FAILURE BY THE MECHANISM OF HYDROGEN-STRESS CRACKING. /AUTHOR/

• Supplemental Notes:
  • Hpr-pr-1 (6), D-6-3
• Corporate Authors:

  Aerojet General Corporation

  9200 East Flair Drive
  El Monte, CA  United States  91734

  California Department of Public Works

  1120 N Street
  Sacramento, CA  United States  95814

  Bureau of Public Roads /US

  400 7th Street, SW
  Washington, DC  United States  20590
• Authors:
  • Niemann, J T
• Publication Date: 1968-7-8

Subject/Index Terms

• TRT Terms: Electrolytic cells; Failure; Hydrogen; Load tests; Prestressing; Sodium chloride; Sodium sulfate; Steel; Stresses; Temperature; Tempering; Tensile strength; Toughness; Traffic delays
• Old TRIS Terms: Demineralized water
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00215892
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS
• Created Date: Nov 29 2003 12:00AM