ABSTRACT
A recently-developed granular road stabilization method was applied to four test sections in different Iowa counties. This new method uses an optimized target gradation achieved by blending existing surface materials with two to three fresh aggregate types to achieve the tightest possible particle packing. A clay slurry is also incorporated into the top two inches during mixing of the surface aggregates to increase the plasticity and binding characteristics to reduce material loss. The performance of the test sections was measured using field dynamic cone penetrometer (DCP) tests, falling weight deflectometer (FWD) tests, and nuclear density gauge tests. The test results are compared to those of adjacent control sections as well as test sections stabilized using Portland cement and steel slag. Among the stabilization methods applied in the test sections, the Optimized Gradation with Clay Slurry stabilization method and the cement-treated 4” surface course was the most costeffective.
