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Full Depth Reclamation with a cement additive has been a preservation solution NCDOT has used to maintain low-volume rural roads for years, and Chris McGee, District #2 Engineer for NCDOT's Division 6, expanded that option in the spring of 2008 by using an emulsion additive on an FDR project in Johnston County.

Baileys X-rds is a collector road with an average daily traffic county of approximately 1,000 vehicles. The farm-to-market road does support a fair amount of truck traffic as well, serving two small trucking companies along with heavy farm equipment. Located south of Raleigh near Dunn, NC, the 23-foot-wide road had severe transverse cracking approximately every 10 feet throughout.

The cracks were from ¼- to ½-inch wide with potholes developing in multiple locations. Several farms and subdivisions are located along this road and it also serves as a connector road for traffic.

A 1.3-mile section of the road between Chic Ennis Road and Ebenezer Church Road was chosen for reconstruction. Sections north and south of the reconstruction project were overlaid with 1.5 inches of HMA only.

"The crack filling followed by an HMA overlay on the north and south sections of Baileys is a typical maintenance approach we take for roads of this type," notes McGee. "The center portion of the road was showing some severe block cracking problems every 30 to 40 feet, similar to what you would find on a concrete road that has an asphalt overlay. Since there was no concrete under the existing asphalt, we wanted to remix the subgrade material and we wanted to see how an emulsion additive versus a cement additive would perform in helping to stabilize the road material."