FATIGUE BEHAVIOR OF CONTINUOUS COMPOSITE BEAMS

THE PROVISIONS OF THE CURRENT /1966/ AASHO BRIDGE DESIGN SPECIFICATIONS FOR COMPOSITE STEEL-CONCRETE BRIDGE BEAMS WAS BASED ON STATIC TESTS AND ALLOWS THE OMISSION OF SHEAR CONNECTORS IN THE NEGATIVE MOMENT REGIONS OF CONTINUOUS COMPOSITE BEAMS WITH CONTINUOUS LONGITUDINAL SLAB REINFORCEMENT. A RECENT STUDY HAS EVALUATED THE FATIGUE STRENGTH OF SHEAR CONNECTORS ON THE BASIS OF MODIFIED PUSHOUT TESTS AND HAS SUGGESTED A DESIGN CRITERIA WHICH WOULD ASSUME ADEQUATE STATIC AND FATIGUE STRENGTH OF SHEAR CONNECTORS IN COMPOSITE BEAMS. THIS STUDY ALSO SUGGESTED THAT SHEAR CONNECTORS WERE REQUIRED IN THE NEGATIVE MOMENT REGIONS OF CONTINUOUS COMPOSITE BEAMS WITH CONTINUOUS LONGITUDINAL REINFORCEMENT. TO EVALUATE THE STUD DESIGN RECOMMENDATIONS, FOUR 2-SPAN, FULL SIZE CONTINUOUS BEAMS WERE DESIGNED AND TESTED UNDER STATIC AND FATIGUE LOADING. THE MAJOR VARIABLES CONSIDERED WERE' /1/ THE EFFECT OF SHEAR CONNECTORS IN THE NEGATIVE MOMENT REGIONS, AND /2/ THE EFFECT OF INCREASED AMOUNTS OF LONGITUDINAL REINFORCEMENT IN THE NEGATIVE MOMENT REGION. THE RESULTS OF THE FATIGUE TESTS ARE PRESENTED IN THIS REPORT. A SUBSEQUENT REPORT WILL PRESENT THE STATIC TEST RESULTS. IT IS CONCLUDED THAT SHEAR CONNECTORS ARE REQUIRED IN THE NEGATIVE MOMENT REGIONS OF CONTINUOUS COMPOSITE BEAMS WITH CONTINUOUS LONGITUDINAL SLAB REINFORCEMENT. IN ADDITION, THE STUDY INDICATED AN INCREASED AMOUNT OF LONGITUDINAL REINFORCEMENT IS REQUIRED IN THE NEGATIVE MOMENT REGION, OVER THAT CURRENTLY ALLOWED BY THE AASHO SPECIFICATIONS, TO IMPROVE INTERACTION AND TO CONTROL SLAB CRACKING. THE FATIQUE TESTS ALSO BROUGHT OUT SEVERAL ADDITIONAL VARIABLES WHICH REQUIRE FURTHER STUDY. THEY ARE DISCUSSED AT THE END OF THE REPORT. /AUTHOR/

• Corporate Authors:

  Lehigh University

  Bethlehem, PA  United States  18015
• Authors:
  • Daniels, J H
  • Fisher, J W
• Publication Date: 1966-12

Subject/Index Terms

• TRT Terms: Beams; Bridge construction; Bridge foundations; Bridges; Composite materials; Construction; Continuous structures; Fasteners; Fatigue (Physiological condition); Fatigue tests; Moments (Mechanics); Reinforcement (Engineering); Shear reinforcement; Static loads; Studs
• Uncontrolled Terms: Composite beams; Continuous beams; Shear connectors
• Old TRIS Terms: Moments; Static loading
• Subject Areas: Bridges and other structures; Construction; Highways;

Filing Info

• Accession Number: 00207833
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Report/Paper Numbers: Prp 41-1
• Files: TRIS
• Created Date: May 25 1994 12:00AM