FORECASTING OF HEAVY LOADING PATTERNS ON HIGHWAY BRIDGES

THE PURPOSE WAS TO DEVELOP A GENERAL THEORY OR MODEL WHICH WILL ACCURATELY FORECAST THE MAGNITUDE AND FREQUENCY OF OCCURRENCE OF HEAVY LOADS ON HIGHWAY BRIDGES. TO FULFILL THIS OBJECTIVE, AN ELECTRONIC COMPUTER SIMULATION MODEL WAS DEVELOPED AND TESTED WHICH WILL PREDICT THE FREQUENCY OF LOAD RANGES THAT MAY BE EXPECTED TO OCCUR ON A BRIDGE OF SPECIFIED LENGTH FOR TRAFFIC VOLUMES WITH KNOWN VEHICLE CHARACTERISTICS AND KNOWN APPROACH ROADWAY GEOMETRY. THE MODEL IS A TIME-STEP SIMULATION WHICH MOVES THE TRAFFIC OVER THE ROADWAY AND ACROSS THE BRIDGE ACCORDING TO KNOWN VEHICLE OPERATING RELATIONSHIPS. AS THE VEHICLES CROSS THE BRIDGE, THEIR AXLE WEIGHTS ARE SUMMED TO DETERMINE THE TOTAL LOAD ON THE BRIDGE DURING EACH TIME INCREMENT. WHEN A MAXIMUM WEIGHT IS DETERMINED, IT IS RECORDED IN THE PROPER LOAD RANGE INTERVAL. THE MODEL WAS VALIDATED BY SIMULATING TRAFFIC OVER A BRIDGE SITE LOCATED ON US ROUTE 301 JUST SOUTH OF MARYLAND ROUTE 4 NEAR UPPER MARLBORO, MARYLAND. THE RESULTS OF THE SIMULATION WERE COMPARED TO ACTUAL TRAFFIC MEASUREMENTS MADE BY THE UNIVERSITY OF MARYLAND WHILE THEY WERE CONDUCTING DYNAMIC STRAIN STUDIES AT THIS BRIDGE SITE. THE SIMULATION RESULTS WERE WELL WITHIN THE RANGE OF EXPECTED VALUES. A SECTION OF THE REPORT IS DEVOTED TO ANALYTICAL METHODS OF EXTENDING THE RANGE OF PREDICTION PROVIDED BY THE SIMULATION MODEL. THE NECESSARY INTERACTION BETWEEN OBSERVATION, SIMULATION, AND ANALYSIS IS DISCUSSED; A SURVEY OF ANALYTICAL MODELS IS PRESENTED; AND EXAMPLES ARE PROVIDED OF COMPUTATIONS WHICH CAN BE MADE DIRECTLY FROM OBSERVATIONAL DATA WHICH LEAD TO LONG-TERM FORECASTS. /AUTHOR/

• Corporate Authors:

  Kelly Scientific Corporation

  705 Owen Street
  Rockville, MD  United States  20850

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Bissell, H
  • Camer, D
  • Eckert, R
• Publication Date: 1970-6

Subject/Index Terms

• TRT Terms: Analysis; Axles; Computers; Forecasting; Highway bridges; Loads; Mathematical models; Simulation; Traffic; Vehicle characteristics; Weight
• Uncontrolled Terms: Loading; Models
• Old TRIS Terms: Time step
• Subject Areas: Bridges and other structures; Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00207960
• Record Type: Publication
• Source Agency: Federal Highway Administration
• Contract Numbers: DOT-FH-11-7314
• Files: TRIS, USDOT
• Created Date: Sep 28 1970 12:00AM