AN INVESTIGATION OF DYNAMICALLY INDUCED STRESSES IN A TYPICAL HIGHWAY BRIDGE

THIS INVESTIGATION IS CENTERED AROUND THE MAGNITUDE OF TENSILE STRESSES IN THE BRIDGE DECKS, CAUSED BY THE NEGATIVE MOMENT PRESENT DURING THE UPWARD DEFLECTION, DUE TO FREE VIBRATIONS RESULTING FROM A VEHICLES PASSAGE. THE INHERENTLY LOW-TENSILE STRENGTH OF CONCRETE, COUPLED WITH A REDUCTION OF STRENGTH DUE TO FATIGUE, POINTED TO THE POSSIBILITY OF INITIATION OF DYNAMICALLY INDUCED CRACKS. ONCE CRACKED, THE DECK COULD BE SUBJECTED TO INCREASED WEATHERING EFFECTS OR ABRASION WHICH WOULD HASTEN DETERIORATION. TO FACILITATE AN ANALYTICAL SOLUTION TO THE PROBLEM AN ELECTRICAL CIRCUIT WAS DESIGNED FOR THE PACE 231 ANALOG COMPUTER IN THE UNIVERSITY OF CONNECTICUTS COMPUTER CENTER. THIS CIRCUIT SIMULATES A DAMPENED, LUMPED MASS, SIMPLE SPAN BRIDGE UNDER THE INFLUENCE OF A SINGLE WHEELED VEHICLE CONSISTING OF A SPRUNG MASS AND AN UNSPRUNG MASS WITH AN EQUIVALENT VISCOUS DAMPING SHOCK ABSORBER. USING THIS ANALOGY A TYPICAL BRIDGE WAS STUDIED TO DETERMINE THE INFLUENCE OF VEHICLE SPEED AND THE PRESENCE OF VARIATIONS IN THE HEIGHT OF THE APPROACH SLAB ON THE ORDER OF MAGNITUDE OF THE RESULTING TENSILE STRESSES. /AUTHOR/

• Supplemental Notes:
  • Rept Jhr-66-4, 46 PP
• Corporate Authors:

  University of Connecticut, Storrs

  Department of Civil and Environmental Engineering, 261 Glenbrook Road
  Storrs, CT  United States  06269-2037
• Authors:
  • Longley, J C
• Publication Date: 1966-7

Subject/Index Terms

• TRT Terms: Abrasions; Analog computers; Approach lanes; Bridge decks; Bridge superstructures; Cracking; Deflection; Deterioration; Electric circuits; Fatigue (Physiological condition); Highway bridges; Magnitude; Simulation; Slabs; Tension; Traffic speed; Vibration; Weathering
• Uncontrolled Terms: Bridge spans; Tensile stress
• Old TRIS Terms: Approaches
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00208273
• Record Type: Publication
• Files: TRIS
• Created Date: May 25 1994 12:00AM