AMBIENT VIBRATION SURVEY OF NEWPORT BRIDGE AND AMBIENT VIBRATION SURVEY OF CHESAPEAKE BAY BRIDGE

THE AMBIENT VIBRATION SURVEY IS A PRACTICAL METHOD OF DETERMINING THE DYNAMIC PROPERTIES OF A STRUCTURE. THE CHARACTERISTIC MODE SHAPES, THEIR ASSOCIATED FREQUENCIES AND THE VALUE OF DAMPING AT LOW VIBRATION LEVELS ARE MEASURED EXPERIMENTALLY. THE NATURAL AND CULTURAL VIBRATIONS, WHICH EXIST AT ALL TIMES, CAUSE STRUCTURES TO RESPOND IN THEIR CHARACTERISTIC MODES OF VIBRATION. BY MEASURING THE EFFECT OF AMBIENT VIBRATIONS ON THE STRUCTURE WITH VERY SENSITIVE SEISMOMETERS, AND ANALYZING THE DATA MATHEMATICALLY, THE DYNAMIC PROPERTIES CAN BE OBTAINED. TWO SUSPENSION BRIDGES WERE SELECTED FOR STUDY; THE NEWPORT BRIDGE, WHICH CROSSES THE NARRAGANSETT BAY IN RHODE ISLAND, AND THE LANE MEMORIAL BRIDGE WHICH CROSSES CHESAPEAKE BAY IN MARYLAND. A SEPARATE REPORT COVERS THE STUDY OF EACH BRIDGE. THE STUDY REVEALED MANY MODES OF VIBRATION BETWEEN 0 AND 60 CPM WHICH WAS THE FREQUENCY RANGE OF INTEREST. THE MODES REPRESENT FOUR DIFFERENT TYPES OF STRUCTURAL BEHAVIOR. THE EXPERIMENT WAS DESIGNED TO CONCENTRATE ON VERTICAL AND TORSIONAL MODES OF THE DECK. THE AMBIENT VIBRATION SURVEY WAS DEMONSTRATED TO BE A PRACTICAL AND EFFECTIVE MEANS OF MEASURING THE DYNAMIC PROPERTIES OF A SUSPENSION BRIDGE. /BPR/

• Corporate Authors:

  Teledyne Geotronics

  ,    

  Bureau of Public Roads /US

  400 7th Street, SW
  Washington, DC  United States  20590
• Authors:
  • Mclamore, V R
• Publication Date: 0

Subject/Index Terms

• TRT Terms: Dynamic tests; Dynamics; Mathematical analysis; Seismometers; Structural analysis; Structural mechanics; Suspension bridges; Vibration
• Uncontrolled Terms: Structural behavior
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00207948
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Report/Paper Numbers: Bpr No Fh-11-7343
• Contract Numbers: DOT-FH-11-7343
• Files: TRIS
• Created Date: Jul 14 1970 12:00AM