IMPORTANCE OF ACTUAL BEHAVIOR IN SHAPING DESIGN CRITERIA

This paper which describes the Corps of Engineers continuing program of pavement condition evaluation, stresses the need to examine the performance of full scale pavements to verify design critieria, and lists 14 modifications to the the Corps' CBR design system. The elements of behavior or design are discussed and include the analytical model which describes the manner in which the parameters controlling design interact; the constitutive behavior which relates the stress, strain or equivalent behavior of the individual elements or materials of which the pavement is constructed; and the terminal condition description considered to represent failure. The CBR test was adapted as a means of assessing the strength of materials in flexible pavements. To provide the comparisons between full scale pavements under traffic with expected behavior as predicted by the design method, the Corps of Engineers undertook two efforts. The first which gives immediate comparisons, in the full scale accelerated traffic tests, many of which have been conducted to establish or extend the CBR design methods. A survey program was undertaken to provide information on the behavior of pavements in serving their intended purpose. Actual pavement characteristics in relation to design considerations (layer thickness, characteristics of materials, strength, bituminous surfacings and stabilized layers, subgrade strength) traffic loading, special contributing factors (such as construction deviations, swelling soil, etc.), and the observable pavement condition should be studied and compared with prior examinations in an attempt to determine at what point in its overall life the pavement is at the time of examination. Based on the data, a design can be projected using existing pavement characteristics, and this will indicate an expected part of the total pavement life to be used.

• Supplemental Notes:
  • Proceedings from a conference on Utilization of Graded Aggregate Base Materials in Flexible Pavements, March 25-26, 1974, Oak Brook Hyatt House, Oak Brook, Illinois.
• Corporate Authors:

  National Crushed Stone Association

  1415 Elliot Place, NW
  Washington, DC  United States  20007

  National Sand and Gravel Association

  900 Spring Street
  Silver Spring, MD  United States  20910

  National Slag Association

  300 South Washington Street
  Alexandria, VA  United States  22314
• Authors:
  • Ahlvin, R G
• Publication Date: 1974

Media Info

• Features: References;
• Pagination: p. VII1-9
• Serial:
  • Publication of: National Crushed Stone Association
  • Publisher: National Crushed Stone Association

Subject/Index Terms

• TRT Terms: Alternatives analysis; Building materials; California bearing ratio; Coarse aggregates; Design; Evaluation; Failure; Fine aggregates; Flexible pavements; Forecasting; Mathematical models; Pavement base course; Pavement design; Pavement performance; Pavements; Testing; Traffic loads
• Uncontrolled Terms: Base; Comparative analysis; Design criteria; Models
• Old TRIS Terms: Cbr testing; Graded coarse aggregate; Graded fine aggregate
• Subject Areas: Design; Freight Transportation; Geotechnology; Highways; Pavements;

Filing Info

• Accession Number: 00127532
• Record Type: Publication
• Files: TRIS
• Created Date: Apr 7 1976 12:00AM