Responses and Performance of Stabilized Full-Depth Reclaimed Pavements at the Minnesota Road Research Facility

Abstract

This paper details the construction and analysis of three stabilized full-depth reclamation (SFDR) sections (Cells 2, 3, and 4) constructed at the Minnesota Road Research Facility on I-94 in 2008. Three test sections with different ratios of pulverized asphalt concrete to granular base were constructed, and the performance of full-depth reclaimed pavements stabilized with engineered emulsion was studied. Emulsion content and base structure varied between test sections. Each test section was designed for 3.5 million equivalent single-axle loads for a period of 5 years. As of June 30, 2012, the sections had been subjected to approximately 2.2 million such loads. Responses were measured with strain gauges embedded at the bottom of the hot-mix asphalt and SFDR layers in each test section. The strain gauges indicated that the bottom of both the hot-mix asphalt and the SFDR layers was subject to horizontal tensile strain from falling weight deflectometer testing and heavy vehicle loading. Pavement performance for rutting, cracking, and international roughness index was measured periodically. The results indicated that all three cells were performing well. The only crack in the three cells was in Cell 3; the roughness index values were well within the acceptable range and rutting, although progressing, was still acceptable. The paper concludes with modeled responses and performance predictions from DARWinME and BISAR. Model predictions indicate that an SFDR layer will provide greater structural benefits and increased performance than will similar structures with unstabilized full-depth reclaimed or granular base layers.