MECHANICAL METHODS OF STEEL PLACEMENT FOR SLIP-FORM CONSTRUCTION OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENTS

THE EXTENT OF THE USE OF MECHANICAL STEEL PLACERS IN THIS COUNTRY WAS EVALUATED THROUGH QUESTIONNAIRES DIRECTED TO SELECTED HIGHWAY OFFICIALS, CORRESPONDENCE AND INTERVIEWS WITH CONTRACTORS AND OTHER HIGHWAY OFFICIALS, AND OBSERVATIONS OF ACTUAL JOBS. THE PROCEDURES FOLLOWED ON SELECTED JOBS WERE RECORDED ON FILM WITH THE AID OF A TIMELAPSE CAMERA, AND THE PHOTGRAPHS WERE LATER USED IN THE ANALYSES OF THE PLACEMENT METHODS AND TECHNIQUES. SEVERAL TYPES OF MESH DEPRESSORS AND BAR PLACERS ARE DESCRIBED. FROM THE OBSERVATION AND THE SUBSEQUENT ANALYSES, THE FOLLOWING SUMMARY COMMENTS ARE MADE: (1) THE NUMBER OF STATES THAT HAVE TURNED TO THE USE OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENTS IS RAPIDLY INCREASING. (2) MACHINES ARE NOW AVAILABLE THAT CAN PLACE STEEL FASTER, AT LESS EXPENSE, AND WITH LESS LABOR THAN THE MANUAL OPERATIONS FORMERLY EMPLOYED. THESE MACHINES HAVE BEEN USED TO THE GENERAL SATISFACTION OF THE STATE HIGHWAY OFFICIALS. (3) SEVERAL STATES HAVE MODIFIED THEIR SPECIFICATIONS SO AS TO ACCOMMODATE PLACEMENT TOLERANCES THAT ARE COMPATIBLE WITH THE MECHANICAL METHODS. (4) MANY STATES HAVE ELIMINATED THE USE OF TRANSVERSE BARS IN THE CONSTRUCTION OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENTS. (5) THROUGH ADEQUATE PLANNING AND THE USE OF MECHANICAL METHODS FOR STEEL PLACEMENT, CONTRACTORS HAVE DEMONSTRATED THAT THEY CAN IMPROVE THE EFFICIENCY OF THEIR STEEL LAYING OPERATIONS. (6) CURRENTLY AVAILABLE MECHANICAL DEVICES FOR DEPRESSING STEEL ARE NOT YET FULLY PERFECTED, BUT ADDITIONAL IMPROVEMENTS CAN BE EXPECTED IN THE FUTURE. AND (7) THE SAVINGS THAT CAN CURRENTLY BE REALIZED FROM THE USE OF MECHANICAL STEEL PLACERS CANNOT BE SPECIFICALLY IDENTIFIED BECAUSE OF LIMITED EXPERIENCE. HOWEVER, THE POTENTIAL SAVINGS CAN BE SUFFICIENTLY ATTRACTIVE TO WARRANT THE INTEREST OF HIGHWAY OFFICIALS.

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  • Supplemental Notes:
    • Sponsored by Committee on Rigid Pavement Construction. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
  • Authors:
    • Scholer, C F
    • Olateju, O T
  • Publication Date: 1972

Media Info

  • Media Type: Digital/other
  • Pagination: pp 1-4
  • Monograph Title: Concrete pavement construction and joint sealants
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00215540
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Sep 19 1972 12:00AM