REPORT OF COMMITTEE ON THE USE OF HIGH ELASTIC STEEL AS REINFORCEMENT FOR CONCRETE: CHAPTER XI. BOND TESTS ON ON RUSTED BARS

REPORT OF COMMITTEE ON THE USE OF HIGH ELASTIC STEEL AS REINFORCEMENT FOR CONCRETE: CHAPTER XI. BOND TESTS PLAIN ROUND 5/8-IN. RAIL STEEL BARS WERE EXPOSED TO THE WEATHER FOR 0,1,2,3,4,6,7, AND 8 MONTHS RESPECTIVELY. RUST FORMATION WAS OBSERVED, AND MEASURED BY ABRADING THE RUST AND WEIGHING IT. ON COMPANION BARS THE RUST WAS: (A) LEFT UNMOLESTED, AND (B) WIPED OFF WITH BURLAP. ALL BARS WERE VERTICALLY CAST INTO 4 BY 4 BY 10-IN. 28-DAY PULLOUT SPECIMENTS (L/D=16) AND OBSERVATIONS WERE TAKEN FOR "FIRST SLIP," ULTIMATE BOND RESISTANCE AND DRAG RESISTANCE AFTER A SLIPPAGE OF 0.08 IN. AMOUNTS OF SLIPPAGE WERE MEASURED AT BOTH THE LOADED AND THE UNLOADED ENDS OF THE BARS. THE GENERAL CONCLUSIONS REACHED ARE THAT THE LIGHT LAYER OF LOOSE POWDERY RED RUST THAT FIRST FORMS IS OF NEGLIBLE IMPORTANCE AND THAT FIRM RUST TENDS TO INCREASE BOND RESISTANCE. AFTER THE RUST BECAME DEEP, LOOSE AND FLAKY, AS FOR THE LONGEST EXPOSURES, BOND WAS REDUCED MODERATELY BUT WIPING THE LOOSE RUST OFF WITH BURLAP MORE THAN RESTORED THE BOND TO THAT OF THE UNRUSTED BAR. TESTS AND MEASUREMENTS SHOW THAT EVEN FOR THE LONGEST EXPOSURES WHICH GAVE DEEP LOOSE LAYERS OF RUST THERE WAS NO SIGNIFICANT REDUCTION IN BAR CROSS-SECTION BECAUSE OF THE RUST. THE VOLUME OF RUST IS MUCH GREATER THAN THAT OF THE STEEL FROM WHICH IT WAS FORMED. THE RESULTS SECURED ARE IN ESSENTIAL AGREEMENT WITH THE LIMITED RECORDED FINDINGS OF THE OTHER INVESTIGATORS LISTED AS REFERENCES. /AUTHOR/

  • Supplemental Notes:
    • Vol 19, pp 148-163, 15 FIG, 6 REF
  • Authors:
    • Gilkey, H J
    • Chamberlin, S J
    • Beal, R W
  • Publication Date: 1940

Media Info

  • Monograph Title: Proceedings of the Nineteenth Annual Meeting of the Highway Research Board Held at Washington, D.C. December 5-8, 1939
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00209418
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Oct 3 1971 12:00AM