DYNAMICS OF HIGHWAY BRIDGES

A THEORETICAL STUDY OF AND EXPERIMENTAL DATA RELATING TO THE DYNAMIC RESPONSE TO MOVING LOADS OF A DECK STEEL GIRDER CONTINUOUS HIGHWAY BRIDGE IS PRESENTED. A STUDY OF THE THEORETICAL STRESSES AND A COMPARISON OF THEORETICAL AND EXPERIMENTAL STATIC AND DYNAMIC STRESSES IS INCLUDED. THE BRIDGE INVESTIGATED IS A SEVEN-SPAN, CONTINUOUS, STEEL-GIRDER BRIDGE WITH TWO REINFORCED-CONCRETE APPROACH SPANS, TOTALING 800 FT. IN LENGTH AND 36 FT. WIDE. THE CONCRETE DECK IS BONDED AND ANCHORED TO THE TOP FLANGE OF THE STEEL GIRDERS. THERE ARE EIGHT LONGITUDINAL STEEL GIRDERS CONNECTED BY RIGID STEEL-GIRDER TRANSVERSE DIAPHRAGMS. FOUR TRANSVERSE DIAPHRAGMS WERE USED IN THE FIVE 100-FT. SPANS AND THREE DIAPHRAGMS IN THE TWO 86-FT. END SPANS. LOADS USED FOR THE TESTS WERE ONE EUCLID EARTH MOVER OF GROSS WEIGHT 51,500 LB., AND ONE LOADED WHITE TRUCK OF GROSS WEIGHT 30,250 LB. ELECTRICAL RESISTANCE, SR-4 STRAIN GAGES WERE USED TO MEASURE STRESSES AT 116 POINTS. BOTH STATIC AND DYNAMIC STRESSES WERE MEASURED. DYNAMIC STRESSES WERE RECORDED ON A CATHODE-RAY OSCILLOSCOPE, WHOSE SCREEN WAS PHOTOGRAPHED. THE MEASURED STATIC STRESSES WERE IN EXCELLENT AGREEMENT WITH THE THEORETICAL STRESSES. THE BASIC ELEMENTARY THEORY USED FOR THE STATIC STRESS ANALYSIS ASSUMED THAT THE DIAPHRAGMS WERE RIGID AND DISTRIBUTED THE LOAD IN ANY LANE TO ALL THE GIRDERS. THE DIAPHRAGMS WERE FOUND TO BE COMPLETELY EFFECTIVE. THE DYNAMIC STRESSES WERE NOT PROPORTIONAL TO THE STATIC STRESSES NOR WERE THEY DISTRIBUTED AMONG THE GIRDERS IN THE SAME WAY. THE TESTS INDICATED THAT THE AASHO IMPACT FORMULA TENDED TO OVERESTIMATE THE IMPACT EFFECT BY ABOUT 50 PERCENT. A TENTATIVE IMPACT FORMULA IS SUGGESTED. /AUTHOR/

• Record URL:
  https://onlinepubs.trb.org/Onlinepubs/hrbproceedings/32/32-011.pdf
• Supplemental Notes:
  • Vol 32, pp 180-187. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Wise, J A
  • Rodgers, T W
  • Vincent, G S
  • Oehler, L T
• Publication Date: 1953

Media Info

• Media Type: Digital/other
• Monograph Title: Proceedings of the Thirty-Second Annual Meeting of the Highway Research Board, Washington, D.C., January 13-16, 1953
• Serial:
  • Highway Research Board Proceedings
  • Volume: 32
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Bridge decks; Bridge members; Diaphragms (Engineering); Dynamic loads; Girders; Highway bridges; Length; Loads; Oscilloscopes; Reinforced concrete; Steel; Strain gages; Structural analysis; Theory
• Uncontrolled Terms: Bridge spans; Dynamic response
• Old TRIS Terms: Cathode ray oscilloscopes; Diaphragms; Electrical strain gages
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00209454
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Aug 15 1971 12:00AM