ABSTRACT
This study examined the effect of the amount of subgrade soil and the cement application rate on the mix design of full-depth reclamation (FDR) blends. Four FDR blends containing varying amounts of subgrade soil (0%, 12.1%, 25.6%, and 40.8% by weight) were included in the laboratory testing plan. The FDR blends were mixed with different cement application rates (4%, 6%, and 8%). The test results showed a higher susceptibility to volumetric changes and lower unconfined compressive strength values for the FDR blends containing higher amounts of subgrade. At a cement application rate of 4%, the FDR blend containing 0% subgrade was the only blend that met a minimum unconfined compressive strength of 300 psi, which is commonly used in the mix design of FDR mixtures. While using a higher cement application rate for the other blends resulted in somewhat higher unconfined compressive strength values, none of these blends was able to achieve a minimum unconfined compressive strength of 300 psi, even at a cement application rate of 8%.
