FATIGUE STRENGTH OF PRESTRESSED COMPOSITE STEEL-CONCRETE BEAMS

Effective prestressing increases the strength of existing composite steel-concrete bridges. Investigators have identified the static strength of prestressed composite girders, but without consideration of fatigue strength--an important design factor in highway bridges. This paper examines 11 prestressed composite beams with cover plates welded to the tension flange and prestressed with two seven-wire strands. When the composite beams were fatigue tested to failure, cracks initiated in the flange at the cover-plate ends. Stress ranges in the strands and at the base of the shear studs were too small to initiate cracks. Prestressing of the steel beam so that the stress in the tension flange shifts between tension and compression under cyclic loading raised the fatigue strength of the welded cover plates by one category, from D to C.

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  • English

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Filing Info

  • Accession Number: 00714672
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Dec 27 1995 12:00AM