This report documents changes made to the Chevron N-layer computer program to:

  1. Include superposition principles.
  2. Calculate strain energy density (or work) at specified locations within the pavement structure.
  3. Analyze pavement response at specified radii from one circularly loaded area to permit comparison of analyses by the program as originally written with results incorporating superposition principles.
  4. Evaluate pavement response to any combination of loads on circular areas defined by XY coordinates on the surface. Loads and contact pressures are permitted to be different from one loaded area to another, but must be constant for any one loaded area.
  5. Simulate dynamic loads as the difference between the root mean squares of the maximum and minimum dynamic loads. This analysis is appropriate for constant vibratory testers such as Road Raters and Dynaflects. Moduli of asphaltic concrete must be adjusted for frequency effects.

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The contents of this report reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, of the Kentucky Transportation Cabinet, or of the Federal Highway Administration, or Chevron Research Company, Standard Oil Company of California. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names and tradenames are for identification purposes and are not to be considered as endorsements.