The review of currently available overlay design methods indicates that these may be grouped in three categories: those based on a visual condition rating, those using NDT deflections and empirically derived relationships between allowable deflection and overlay needs, and semirational procedures using stress analysis. The more promising of these procedures were subjected to detailed analysis and compared using data from a variety of projects. The result of this analysis show that none of the existing models is very satisfactory and that a new overlay design procedure is needed. This paper presents the formulation of a method that attempts to overcome the difficulties and limitations of current methods. The proposed method utilizes both NDT and visual condition evaluation as well as limited destructive and laboratory testing to evaluate existing pavement condition. A coupled FEM-multilayer elastic subgrade program is used in stress analysis, and the amount of overlay is determined based on limiting formation of load-induced fatigue cracking. This program will be used in a re-examination of the AASHO Road Test data as well as other available performance data to identify and correlate available field data with a performance distress function. Reflection cracking analysis incorporating load-induced shear as well as temperature induced stresses (both horizontal and curling stresses) will be used to minimize the probability of reflective crack formation. (Author)

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 43-53

Subject/Index Terms

Filing Info

  • Accession Number: 00334240
  • Record Type: Publication
  • Report/Paper Numbers: Proceeding
  • Files: TRIS, USDOT
  • Created Date: Sep 16 1981 12:00AM