Continuously reinforced concrete overlays on existing Portland cement concrete pavements

Three thicknesses of overlay and two separate amounts of longitudinal reinforcement were used in the experimental sections. Observations and measurements were carried out over a 10 year period to evaluate the behavior of the experimental overlays under I-80 regular mixed traffic. During that period the pavements carried in excess of 7,000,000 equivalent 18-kip single-axle load applications with very little change in riding quality or level of service, without requiring any structural maintenance. Transverse cracking followed the normal trend for regular CRC pavement, and edge deflections were very small for all test sections. Changes in transverse crack width from summer to winter were small for all sections, and decreased with increasing slab thickness. Recommendations are included for design and construction of overlays relative to minimum overlay thickness, amount of longitudinal steel, use of a bituminous leveling course as a bond breaker, and tolerances for overlay thickness control during construction.