SUMMARY REPORT ON THERMAL STRESSES IN HIGHWAY BRIDGES

THE REPORT SUMMARIZES A THEORETICAL AND EXPERIMENTAL INVESTIGATION OF THE STRESS DISTRIBUTION IN HIGHWAY BRIDGES CAUSED BY A THERMAL GRADIENT. THREE TYPES OF BRIDGES WERE INVESTIGATED EXPERIMENTALLY' COMPOSITE STEEL AND CONCRETE BRIDGES, REINFORCED CONCRETE MONOLITHIC BEAM AND SLAB BRIDGES, AND FOUR VARIATIONS OF PRESTRESSED CONCRETE I-BEAM BRIDGES. THE FIELD STUDIES INVOLVED THE SIMULTANEOUS RECORDING OF STRAINS AND TEMPERATURES AT VARIOUS EXTERIOR AND INTERIOR POINTS ON THE BRIDGES FOR SEVERAL SEASONS. A PORTION OF ONE BRIDGE WAS INSULATED WITH URETHANE FOAM IN ORDER TO STUDY THE EFFECT OF SUCH INSULATION ON THE THERMAL STRESSES. EMPIRICAL AS WELL AS RIGOROUS THEORETICAL EQUATIONS WERE DEVELOPED IN ORDER TO PREDICT THE THERMAL BEHAVIOR OF EACH BRIDGE TYPE. SOME CONCLUSIONS BASED ON THIS STUDY ARE AS FOLLOWS' 1. IN COMPOSITE BRIDGES, STRESSES AS HIGH AS 3000 PSI CAN RESULT FROM A THERMAL GRADIENT OF 25 DEGREES F. LARGER DIFFERENTIAL TEMPERATURES WOULD INDUCE HIGHER STRESSES, AND IT IS CONCEIVABLE THAT DESIGN ALLOWABLE STRESSES COULD BE EXCEEDED IF THERMAL STRESSES ARE COMBINED WITH DEAD LOAD, LIVE LOAD AND SHRINKAGE STRESSES, 2. IN PRESTRESSED CONCRETE BEAMS, SUBJECTED TO NORMAL CYCLIC SOLAR AND ATMOSPHERIC FLUCTUATIONS, THE THERMALLY INDUCED STRESSES APPEAR TO BE ABSORBED BY CURRENT DESIGN PROCEDURES AND SAFETY FACTORS, AND 3. IN MASSIVE REINFORCED CONCRETE BRIDGES, THERMALLY INDUCED STRESSES SEEM TO PRESENT NO SERIOUS PROBLEM. /BPR/

• Corporate Authors:

  Virginia Highway Research Council

  Charlottesville, VA  United States 
• Authors:
  • Zuk, W
• Publication Date: 1965-10

Subject/Index Terms

• TRT Terms: Beams; Composite construction; Deformation curve; Electric insulating materials; Equations; Field studies; Highway bridges; I beams; Insulating materials; Monoliths; Prestressed concrete; Prestressing; Reinforced concrete bridges; Slabs; Strain (Mechanics); Temperature; Theory; Thermal stresses; Urethane
• Old TRIS Terms: Empirical equations; Strains
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00207780
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Report/Paper Numbers: Hpr-1/27/
• Files: TRIS
• Created Date: Mar 1 1994 12:00AM