CONCRETE OVERLAYS FOR CONCRETE AND ASPHALT PAVEMENTS

Concrete resurfacing of worn concrete pavements has been a fairly common practice in the United States for more than 60 years. Since the mid- 1950's new construction on the Interstate System has taken precedence, and fewer concrete resurfacing projects were built. With the emergence of the 3R program of pavement rehabilitation, restoration and resurfacing, new interest is being shown in the use of concrete as a more durable and permanent resurfacing material. A recent survey (1977) of 39 concrete resurfacing projects in the U.S. with plain or conventionally reinforced designs showed them ranging from 4 to 36 years of age, with an average age of 25 years. Their designs varied considerably; more than a third of the projects were plain concrete without reinforcement or dowels. The results of a 1975 survey of 23 CRC projects are reviewed and brought up to date with 1980 condition data. Designs using a thin layer of concrete bonded to the old slab have been employed as a resurfacing method in the U.S. for many years. The results of bridge deck resurfacing using a dense concrete mix have been particularly successful. The resurgence of interest in concrete pavement resurfacing has brought new emphasis on techniques and equipment to adapt this method to the level of other full-scale high speed paving operations. Current concrete resurfacing activities in the U.S. show a noticeable trend toward the use of concrete overlays to restore worn bituminous pavements.