Improving Embankment Design and Performance

This project involved compacted soil and the prediction of its behavior. Two soils were examined (A-4, A-7-6), with 2 rollers each; 2 test pads were included in the methodical examination of behavior. Exhaustive testing was performed of both laboratory and field compacted conditions. Procedures were created that allow: 1) creation of a design specification for compaction that will assure a desired field behavior parameter; 2) prediction of the field parameters knowing only inspection testing results; 3) accounting for variability in parameters in design analyses. These procedures are significant additions to the state-of-the-art. In all cases of parameters, magnitudes of water content and dry density, as-compacted, must be controlled or known. The range of water content, as-compacted, plays a major role in property variability. These findings led to recommendation for a re-examination of Indiana specifications to provoke more thorough regulation of dry density and water content; only in this way can there be assured control of behavior in-service, the pre-requisite to minimizing the need for premature maintenance. An enlargement of the data base is recommended by an implementation program.