DETERMINING THE MAXIMUM PERMISSIBLE WEIGHTS OF VEHICLES ON BRIDGES

THIS REPORT PRESENTS A METHOD OF DETERMINING THE MAXIMUM PERMISSIBLE WEIGHTS OF VEHICLES (BRIDGE FORMULA), WHICH IS RECOMMENDED AS A BASIS FOR VEHICLE WEIGHT REGULATION. THE AXLE WEIGHTS OF A VEHICLE ARE FIRST CONVERTED INTO A LOAD OF IDENTICAL GROSS WEIGHT UNIFORMLY DISTRIBUTED OVER AN EQUIVALENT BASE LENGTH, SO THAT THE EQUIVALENT LOAD GENERATES THE SAME MAXIMUM BENDING MOMENTS OR SHEAR FORCES IN SIMPLY SUPPORTED BEAMS AS THOSE PRODUCED BY THE INDIVIDUAL AXLE WEIGHTS. THUS, THE GROSS WEIGHT OF AXLE GROUPS IS REPRESENTED AS A FUNCTION OF THE EQUIVALENT BASE LENGTH. THIS LOAD FUNCTION IS THEN TRANSFORMED INTO A LARGER LOAD TO BE DISTRIBUTED OVER THE SPAN LENGTH OF SIMPLY SUPPORTED BEAMS. THE CRITICAL MAGNITUDE OF THESE TRANSFORMED LOADS CAN BE DETERMINED FOR SPECIFIC STRUCTURAL TYPES AT TOLERABLE LEVELS OF OVERSTRESS. IN THIS WAY, GROSS WEIGHT ACCEPTANCE LINES CAN BE DEVELOPED AS FUNCTIONS OF EQUIVALENT BASE LENGTHS, BASED ON DEFINITE CONDITIONS OF STRUCTURAL DESIGN. IT IS DEMONSTRATED THAT THESE ACCEPTANCE LINES ARE ALSO VALID WITH REGARD TO CONTINUOUS BRIDGE STRUCTURES. THESE GROSS WEIGHT ACCEPTANCE LINES ARE USED TO TEST AXLE GROUP WEIGHTS OF HEAVY VEHICLES WITH RESPECT TO BRIDGE STRENGTH, BY MEANS OF THEIR EQUIVALENT BASE LENGTH. ARRANGEMENTS OF AXLE LOADS CAN BE OPTIMIZED TO OBTAIN MAXIMUM PAY LOADS FOR VEHICLES. IT IS SUGGESTED THAT THESE OPTIMIZED LOADS COULD BE DISPLAYED ON A LICENSE FORM. /AUTHOR/

  • Supplemental Notes:
    • Rpt No Rr 175, 67 PP, 34 FIG, 6 TAB, 7 REF, 3 APP
  • Corporate Authors:

    Ontario Dept Transp & Communications

    ,    
  • Authors:
    • JUNG, F W
    • Witecki, A A
  • Publication Date: 1971-12

Subject/Index Terms

Filing Info

  • Accession Number: 00209596
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 2 1972 12:00AM