Cold In-Place Recycling on US-283 in Kansas

In 1997 an experimental partial-depth cold in-place recycling project was performed on US-283 in Kansas. Two sections approximately equal in length, one with Class C fly ash and the other with an emulsion with lime slurry, were recycled. On both sections a hot-mix asphalt overlay was placed after curing. Field observations in 1998 showed minor transverse cracking in the fly ash section, but no cracking was evident in the emulsion-plus-lime section. Transverse cracking increased in the fly ash section in 1999 and was noted for the first time in the emulsion-plus-lime section during this same evaluation. Longitudinal cracking in the wheel-paths of the fly ash section was also first observed in 1999. Rutting was not observed in either section during the evaluations. The results of Superpave indirect tensile testing in the laboratory confirmed that the fly ash section should crack before the emulsion-plus-lime section; laboratory testing with the Superpave shear tester and the asphalt pavement analyzer also indicated that the mixtures were not susceptible to rutting.