PRESTRESSED CONCRETE HIGHWAY PAVEMENT AT DULLES INTERNATIONAL AIRPORT

A PRESTRESSED CONCRETE HIGHWAY PAVEMENT WAS CONSTRUCTED IN LATE 1971 AT THE DULLES INTERNATIONAL AIRPORT NEAR WASHINGTON, D.C. THE PAVEMENT IS 3,200 FT LONG AND CONSISTS OF SIX SLABS RANGING IN LENGTH FROM 400 TO 760 FT. THE CONCRETE IS 6 IN. THICK AND 24 FT WIDE. MEASUREMENTS MADE DURING CONSTRUCTION, AND FOR 3.5 MONTHS THEREAFTER, INCLUDED CONCRETE STRENGHTS, STRAND ELONGATIONS DURING STRESSING, CONCRETE TEMPERATURES AND GRADIENTS, SLAB MOVEMENTS, AND PROFILE CHANGES. IN ADDITION, PRIOR TO OPENING TO TRAFFIC, THE PAVEMENT WAS SUBJECTED TO CONTROLLED TESTS WITH AXLE LOADINGS OF 20 AND 33 KIP AT JOINTS AND EDGES WHILE DEFLECTIONS AND STRAINS WERE MEASURED. THE PRESTRESSING TENDONS ARE 1/2-IN. DIAMETER 7-WIRE STRANDS SPACED AT 24 IN. AND TENSIONED TO 29 KIP BY JACKING AT BOTH ENDS OF EACH SLAB. IN ORDER FROM THE WEST END, THREE SLABS 400, 500, AND 600 FT LONG WERE PRESTRESSED WITH THE STRAND IN SMOOTH-WALL STEEL TUBING THAT WAS GROUTED AFTER STRESSING , AND THREE SLABS 760, 500, AND 400 FT LONG WERE PRESTRESSED WITH POLYPROPYLENE-ENCASED, GREASED STRANDS. FRICTION IN THE ENCASEMENTS PRODUCED AVERAGE STRAND EFFECTIVENESS OF 90 PERCENT FOR THE STRAND IN STEEL TUBING AND 80 PERCENT FOR THE PLASTIC-ENCASED STRAND. THE STRANDS PLACED AT 0.5 IN. BELOW MIDDEPTH PRODUCE A FAVORABLE STRESS DISTRIBUTION AND KEEP THE SLAB ENDS FROM WARPING UPWARD. THE DOUBLE LAYER OF POLYETHYLENE OVER THE CEMENT-TREATED SUBBASE ALLOWS DAILY SLAB END MOVEMENTS FROM 0.2 TO 0.4 IN., INDICATING A MAXIMUM DIURNAL FRICTION COEFFICIENT OF LESS THAN 0.5.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 1-19
  • Monograph Title: Pavement systems analyses
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00206129
  • Record Type: Publication
  • ISBN: 0309022509
  • Files: TRIS, TRB
  • Created Date: May 15 1974 12:00AM