The reptitions of tandem axleloads applied to the AASHO Road Test were analyzed by the same method previously reported in analyzing the corresponding single axleload data. The essential findings were: 1. One repetition of a 34-kip (151-kN) tandem axleload appears to cause the same damage as one repetition of an 18-kip (80-kN) single axleload. 2. The relationship of log repetitions versus axleload used by Kentucky appear to be equally valid for single and tandem axleloads. 3. The use of superposition principles, and equivalency of repetitions, in combination with terminal serviceability indiced permitted analyses of the tandem axleload data and comparison with equivalent Kentucky thickness designs converted to the AASHTO structural number. 4. The single axleload analyses were combined with the tandem axleload analyses and superimposed by Kentucky equivalent designes. The Kentucky designs, based upon elastic theory, encompassed 89 percent of the AASHO Road Test data.

Report Date


Report Number

No. 473

Digital Object Identifier



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