LATERAL DISTRIBUTION OF LOAD FOR BRIDGES CONSTRUCTED WITH PRESTRESSED CONCRETE I-BEAMS

THE FIELD TESTING OF AN IN-SERVICE PRESTRESSED CONCRETE I-BEAM BRIDGE SUPERSTRUCTURE IS DESCRIBED. THE SIMPLE-SPAN BRIDGE WAS LOADED WITH A SINGLE TEST VEHICLE WHICH CLOSELY SIMULATED THE HS20-44 DESIGN VEHICLE. THE VEHICLE WAS DRIVEN IN NINE SPECIFIED TEST LANES WHICH EXTENDED LATERALLY ACROSS THE ENTIRE ROADWAY WIDTH. RUNS WERE CONDUCTED AT CRAWL SPEED TO SIMULATE THE STATIC LOAD CONDITION, AT SPEEDS RANGING FROM 5 TO 60 MPH TO PRODUCE THE EFFECTS OF A MOVING VEHICLE, AND AT 10 MPH WITH A 2-INCH RAMP TO SIMULATE A SEVERE IMPACT CONDITION. TWO SERIES OF TEST RUNS WERE CONDUCTED, THE FIRST WITH MIDSPAN DIAPHRAGMS IN PLACE, THE SECOND WITH THE MIDSPAN DIAPHRAGMS REMOVED. THE RESULTS REVEALED THAT THE LOAD DISTRIBUTED (1) TO THE INTERIOR BEAMS WAS LESS THAN THE DESIGN VALUE; (2) TO THE EXTERIOR BEAM UNDER THE CURB SECTION WAS GREATER THAN THE DESIGN VALUE; AND (3) TO THE EXTERIOR BEAM HAVING NO CURB SECTION WAS EITHER GREATER OR LESS THAN THE DESIGN VALUE, DEPENDING ON THE DEFINITION OF THE DESIGN LOAD LANES. IN ADDITION, IT WAS FOUND THAT THE MIDSPAN DIAPHRAGMS ONLY SLIGHTLY INFLUENCED THE EXPERIMENTALLY-BASED DISTRIBUTION FACTORS, PRODUCED BY MULTI-LANE LOADING TO PRODUCE MAXIMUM EFFECTS. HOWEVER, FOR A SINGLE VEHICLE LOAD, THE DIAPHRAGMS DID SERVE TO DISTRIBUTE THE LOAD SOMEWHAT MORE EVENLY. /FHWA/

  • Corporate Authors:

    Lehigh University

    Bethlehem, PA  United States  18015

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • VanHorn, D A
    • Chen, C H
  • Publication Date: 1971-10

Media Info

  • Pagination: 128 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00208046
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Files: TRIS, USDOT
  • Created Date: Jun 28 1972 12:00AM