A design subsystem is presented to estimate the amount of permanent deformation (rutting) resulting from repeated traffic loading. Relationships between applied stress and permanent strain defined by repeated load triaxial compression tests are presented for fine-grained soils, granular materials, and asphalt concrete. Stresses resulting from wheel loads are estimated assuming pavements to be represented as layered elastic structures. The stresses, in turn permit estimation of permanent deformation in each layer of a specific pavement by: (1) Computing the permanent strain at a number of points within the layer, the number being sufficient to define the strain variations with depth. (2) Estimating the deformation by summing the products of the average permanent strains and the corresponding differences in depths between the locations at which the strains were determined. Total rut depth is estimated by summing the contributions from each layer. To illustrate the potential applicability of the procedure, comparison of are amount of rutting with that observed in an in-service pavement is presented. In addition, to illustrate how the method can be used in practice, a number of examples are included, representative of both unsurfaced (low volume) and surface roads. /Author/

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 529-539

Subject/Index Terms

Filing Info

  • Accession Number: 00170236
  • Record Type: Publication
  • Report/Paper Numbers: Proceeding
  • Files: TRIS
  • Created Date: Mar 14 1978 12:00AM