LEGAL LOAD RESTRICTIONS ON INDIVIDUAL AXLES AND GROUPS OF AXLES ARE DISCUSSED IN RELATION TO BRIDGE STRUCTURES. A COMPARISON IS MADE OF THE DIFFERENT TYPES OF AXLE SPACING/MASS SCHEDULES USED TO RESTRICT GROUP AXLE LOADS. STRUCTURAL IMPLICATIONS ARE OUTLINED, AND A THEORETICAL METHOD FOR COMPARING SCHEDULES IS PRESENTED. A SYSTEMATIC PROCEDURE IS DESCRIBED WHICH DETERMINES THE MOST ADVERSE EFFECTS ON BRIDGE STRUCTURES ARISING FROM THE ENFORCEMENT OF A GIVEN SET OF LEGAL RESTRICTIONS ON A NUMBER OF TRUCKS OF SPECIFIED GEOMETRY. THE THEORETICAL CONSIDERATIONS BEHIND THE AXLE SPACING/MASS SCHEDULE PROPOSED BY THE NAASRA ECONOMICS OF ROAD VEHICLE LIMITS STUDY ARE DISCUSSED. RESULTS OBTAINED BY USE OF A COMPUTER PROGRAM FOR A NUMBER OF STUDIES ON THE PROPOSED LOAD LIMITS AND POSSIBLE EXEMPTIONS ARE PRESENTED. THE PAPER CONCLUDES WITH A SUMMARY OF THE MAIN POINTS AND THE CONCLUSIONS REACHED IN DERIVING A NEW AXLE SPACING/MASS SCHEDULE FOR THE AUSTRALIAN SITUATION. (A). FOR THE COVERING ABSTRACT OF THE CONFERENCE PROCEEDINGS SEE IRRD ABSTRACT NO 226354.
Abstract