This report describes a number of gages developed to measure the location and magnitude of ruts. These were installed in a newly constructed asphaltic concrete pavement. They measure lateral deflections and transient and permanent vertical deflections. Some preliminary vertical deflections are reported. An investigation of materials is also reported. The asphalt concrete base, dense-graded aggregate base, and subgrade material were characterized by (1) shear strength (triaxial tests), (2) rheologic behavior (creep tests), (3) permanent deformation characteristics (repeated-load and creep tests), (4) Young's modulus (resonant column tests), and (5) resilient properties (repeated-load tests). Empirical functions were formulated to describe the permanent deformation characteristics of all three materials.

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No. 502

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The contents of this report reflect the views of the author who is responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Bureau of Highways. This report does not constitute a standard, specification, or regulation.