A STUDY OF LOAD DISTRIBUTION CHARACTERISTICS OF SINGLE AND LAYERED TIMBER BRIDGE DECKS SUPPORTED BY MULTIPLE STRINGERS

A THEORETICAL METHOD WAS DEVELOPED TO ANALYZE THE LOAD DISTRIBUTION CHARACTERISTICS OF MULTISTRINGER BRIDGES, INCORPORATING THE STIFFNESS MATRIX METHOD AND THE THEORY OF HARMONIC ANALYSIS. THE METHOD WAS QUITE ADAPTABLE TO ELECTRONIC COMPUTATION. TESTS WERE CONDUCTED ON MODELS OF THREE DIFFERENTLY CONSTRUCTED TIMBER BRIDGE DECKS TO OBTAIN THEIR LOAD DISTRIBUTION CHARACTERISTICS FOR COMPARISON WITH THOSE OBTAINED FROM THE THEORETICAL METHOD. THE EXPERIMENTAL VALUES OBTAINED FOR THE INTERIOR STRINGERS ARE EXPRESSED AS A PERCENTAGE OF THE PREDICTED VALUES, AND WHEN LISTED IN ASCENDING ORDER OF TRANSVERSE FLEXURAL STIFFNESS OF THE MODEL DECKS THE PERCENTAGES WERE APPROXIMATELY 88 PERCENT, 93 PERCENT, AND 95 PERCENT. THE AASHO DISTRIBUTION FACTORS APPEARED TO BE QUITE CONSERVATIVE BASED ON THE EXPERIMENTAL RESULTS REPORTED. THIS CONSERVATISM SUGGESTED THAT THE LAYERED DECK BEING USED BY THE NORTH CAROLINA STATE HIGHWAY COMMISSION COULD SAFELY CARRY AN OCCASIONAL OVERLOAD OF ABOUT 50 PERCENT. THE SIMILARITY OF THE DISTRIBUTION FACTORS OBTAINED FOR THE THREE TYPES OF DECK TESTED INDICATED THAT THE SELECTION OF THE MOST DESIRABLE DECK SYSTEM WOULD PROBABLY BE CONTROLLED BY OTHER DESIGN CONSIDERATIONS, SUCH AS MAINTENANCE OR UNIT COST. /BPR/

• Supplemental Notes:
  • Hpr-1/1/, JUN64
• Corporate Authors:

  North Carolina State University, Raleigh

  Raleigh, NC  United States  27695
• Authors:
  • Zia, P
  • Wilson, W T
  • Rowan, W H
• Publication Date: 1964-6

Subject/Index Terms

• TRT Terms: Alternatives analysis; Bridge decks; Bridge design; Bridges; Development; Fourier analysis; Load transfer; Matrices (Mathematics); Methodology; Pavement layers; Stiffness; Stringers; Structural design; Theory; Timber construction
• Uncontrolled Terms: Model tests
• Old TRIS Terms: Multistringer bridges; Stiffness methods (Structural)
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00207731
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS
• Created Date: Oct 1 1994 12:00AM