Wilkin County, Minn., has stabilized an estimated 80 miles of gravel surface roadways and 30 miles of full-depth reclamation projects with the same base stabilizer. The county had a stabilized full-depth reclamation project scheduled for Wilkin County Highway #8 in 2014.
"Due to some unforeseen circumstances, the project was pushed into late fall and there was not enough time to do the second pass and inject the stabilizer,” Assistant County Engineer Steve Neppl said. “As a result, the road was reclaimed and the unstabilized material was compacted with a pad foot for initial compaction. The surface was shaped with a motor grader and compacted to density with a rubber-tired roller. The project was then halted until the following year.”
In the spring of 2015, information from the Frozen Soil Profile (FSP) was used, which includes charts that track the freeze/thaw cycle within a given year. The road was tested on April 17, 2015. American Engineering & Testing, Inc. conducted a falling weight deflectometer (FWD) test and used ground penetrating radar to collect data on the unstabilized roadway. In the summer of that same year, the top 8 in. of the base material was injected with the BASE ONE base stabilizer from Team Lab Chemical Corp. According to Neppl, a pad foot compactor followed for the initial compaction, and the surface was shaped with a motor grader and compacted to density with a rubber-tired roller. The project was completed by adding a 5.5-in. bituminous surface.
Using the data from the FSP, the road was tested on April 21, 2016—in the same month within four days of the test from the previous year. American Engineering & Testing Inc. conducted a falling weight deflectometer (FWD) test and used ground penetrating radar on the roadway to collect data. The results are shown in the table below.
The project gave Wilkin County a unique opportunity to see how full-depth reclamation (without the stabilizer) and stabilized full-depth reclamation performed on the same road, during the same time of the year after the spring thaw. In all categories, the stabilized material outperformed the non-stabilized material on the tested roadway.
