PAVEMENT DESIGN FOR PERMAFROST CONDITIONS: STRUCTURAL AND THERMAL REQUIREMENTS

The existing Arctic road network is made up almost completely of gravel-surfaced secondary roads for which design, construction, and maintenance procedures are adequate. Proposed reconstruction and paving of the Alaska Highway in the next decade has raised several questions about the adequacy of pavement-design technology for permafrost areas. Because of the nature of permafrost terrain the problems of pavement design are twofold: provision of a structurally sound, smooth pavement to allow safe passage of vehicles during critical thaw periods and prevention of thermal degradation of the subgrade and right-of-way. Recent research has concentrated on the evaluation of new materials and design configurations that minimize subgrade thaw settlement. Research into the structural performance of pavements on permafrost has been minimal. Identification of the strucural and thermal bases for pavement design in permafrost areas is a key requirement for the development of a design technology that includes economic analysis and evaluation. This paper examines the effects of environment, materials, and loading on the thermal and structural responses of insulated and conventional pavement designs on discontinuous permafrost. The vertical temperature and stress distribution for a range of feasible designs was analyzed by means of two computer programs. Dynamic traffic loading of the structures investigated did not produce excessive subgrade strains. However, the dead load of the structure contributed greatly to thaw consolidation of the subgrade. None of the designs completely prevented subgrade thaw. A trade-off between dead load of the structure and thermal protection of the subgrade was identified. This conclusion provides a new justification for the use of low-density insulating layers in pavements on unstable permafrost. (Author)

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 30-35
  • Monograph Title: Evaluation and Analysis of Flexible Pavement Components and Properties
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00322994
  • Record Type: Publication
  • ISBN: 0309030684
  • Files: TRIS, TRB
  • Created Date: Apr 15 1981 12:00AM