The Construction and Performance of CRCP with Flexarm
Continuously reinforced concrete pavements (CRCP) have been constructed in the United States for many years. In fact, the first experimental CRCP was constructed 70 years ago on the Columbia Pike near Washington, D.C., and carried traffic for over 18 years. Further construction of experimental CRCP, notably in 1925 (Public Roads Administration), 1938 (Indiana), 1946 (Illinois), 1947 (New Jersey), and 1951 (Texas), considered the influences of the percent of steel and thickness of the slab, and helped to refine the techniques associated with the design of these pavements. These study sections, and additional insight gleaned from experiences with pavements constructed in California, Maryland, Pennsylvania, and Mississippi in the late 1940’s and early 1950’s, helped to make continuously reinforced pavements an accepted pavement type to carry heavy highway loadings in the United States.
Despite this history of successful performance, CRCP was only introduced in Europe in 1967, on a project on the Belgian Motorway (1). However, since then, its use has grown to the point where continuously reinforced concrete is a widely used pavement type in at least Belgium, France, Italy, and Spain. It is especially popular for use on new roadways intended to carry heavy loads, or for unbonded overlays.
The first CRCP project in France was a reconstruction project by the Paris-Rhine-Rhone Motorways Company (SAPRR), a semi-public toll authority, on the A6 southeast of Paris, in 1983. CRCP was first used in new construction by COFIROUTE, also a semi-private toll authority, in 1986 on the A71, just south of Orleans. The use of CRCP in France has since grown to include more than 20 projects during the period from 1985 to 1991, involving both pavement widenings and new construction. SAPRR has also made extensive use of CRCP, including both reconstruction projects, new construction, and unbonded overlays.
In the application of CRCP in France, a number of problems have been encountered. One of the major concerns is that the layout and the fastening of the reinforcing bars requires a very long work train. The logistics of such a work site can be cumbersome and complex, and occasionally have been considered as a drawback to the selection of continuously reinforced pavements as the alternative of choice.
Presented at the 5th International Conference on Concrete Pavement Design and Rehabilitation in 1993.
Authors: David G. Peshkin, Michael I. Darter, and Jacques Aunis