The method of obtaining the layer moduli reported in this paper relies on the use of layered elastic theory computer programs. It is necessary that the thickness and Poisson's ratio be known for each layer, although the results are not highly sensitive to the value assumed for Poisson's ratio. In the method, points on a two-dimensional surface deflection basin are fitted to the field data. Iteration is required to align the measured and computed points by adjusting the assumed values for the layer moduli. Presently the method relies on trial and error iteration using the BISTRO computer program. It is suggested that a new program be developed which, would enable a more direct determination of the moduli. A case study is presented to demonstrate the application of the method to the evaluation of a test pavement for a heavy duty haul road to support 400,000-pound gross vehicle weight lignite coal trucks. Deflections of the test pavements were obtained using the Dynaflect apparatus and a fully loaded haul vehicle. The major difference in the magnitude of surface loading served to illustrate that the assumption of linear elasticity is not valid over such a range. The evaluation of one of the eight test pavements is illustrated by example, and it is predicted that the pavement will not be satisfactory for the anticipated loading and traffic. The prediction was borne out after several years of use. /Author/

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 831-840

Subject/Index Terms

Filing Info

  • Accession Number: 00170251
  • Record Type: Publication
  • Report/Paper Numbers: Proceeding
  • Files: TRIS
  • Created Date: Mar 29 1978 12:00AM