Two approaches for evaluating the structural capacity of asphalt concrete pavements from nondestructive deflection data are presented in the newly revised AASHTO guide. Both procedures should ideally yield similar results, but studies to confirm this have not been performed. This paper describes a study undertaken by the authors to compare the two techniques. Deflection data from 1,049 tests performed on 55 homogeneous pavement sections were used. Structural capacities were calculated according to both AASHTO techniques in terms of the structural number (SN) value. On the basis of comparisons of the resulting SN values, it was concluded that both AASHTO techniques predict similar capacities. However, the computational time, required effort, and amount of information generated by each method are significantly different. Therefore, selection of the particular evaluation technique for use in a given project should be based on a clear understanding of the type of information required.
Samenvatting