Bonded concrete overlays of jointed concrete pavements currentlyare not used widely for pavement rehabilitation. As part of a majorfhwa research project, between 1987 and 1988 an extensive performance evaluation of 16 different bonded overlay designs at 10 locationsin 6 states was carried out. The projects were located in three different environmental zones and involved a variety of low- to high-volume pavements. The overlays ranged in age from 3 to 11 years at thetime of the surveys. The field performance surveys consisted of thefollowing elements: a comprehensive field survey to identify, measure, and map pavement surface distresses; a debonding survey; the measurement of roughness and a panel present serviceability rating; deflection testing with a falling weight deflectometer; and a materialstesting and sampling program. Historical traffic data were collected to estimate the accumulated 18-kip equivalent single axle loads (esals) on the pavement before and after the overlay was placed. Environmental data were also collected to describe the nature of the environmental forces to which the various sections were subjected. Previous research projects or state reports were reviewed to characterize the construction conditions and the preoverlay condition of the pavements. The results of the field survey are presented for each pavement section based on all of the major measured parameters. Overall, it was found that bonded concrete overlays showed mixed success. Some of the projects appeared to be nearing failure, based on the accumulation of surficial distresses and the apparent widespread debonding that was observed. In general, it was found that debonding was cause for concern on many of the projects. This paper appears in transportation research record no. 1286, Design and evaluation of rigid and flexible pavements 1990.
Abstract