Resilient Moduli of Typical Missouri Soils and Unbound Granular Base Materials

The objective of this project is to accurately determine the resilient moduli for common Missouri subgrade soils and unbound granular base materials in accordance with the AASHTO T 307 test method. The test results included moduli data from 27 common subgrade soils out of the 99 Missouri soil associations and from 5 unbound granular bases. These materials were tested at their optimum water content and at an elevated water content, which would normally occur as a worse case scenario during the life of a pavement. The five unbound granular base materials were tested at two different gradations (high and low side of the Type 5 specification limits) as well as the aforementioned two water contents. Data are provided in the technical report format with all applicable tables and graphs. With the Missouri Department of Transportation (MoDOT) beginning to implement the new Mechanistic-Empirical (M-E) Design Guide for New and Rehabilitated Pavements, the project has accomplished determination of resilient modulus of subgrade soils and unbound granular bases materials used by MoDOT in its flexible pavements. The results of this project allow MoDOT pavement engineers to calibrate the design guide according to Missouri\u27s conditions and materials