Engineering Commons^™

Characteristics And Engineering Properties Of The Soft Soil Layer In Highway Soil Subgrades, Tommy C. Hopkins, Tony L. Beckham, Liecheng Sun

Kentucky Transportation Center Research Report

The objective of this research was to examine the conditions and characteristics of soil subgrades that had been stabilized using mechanical compaction. Goals of the study are to identify and examine the engineering properties and behavior of the “soft layer’ of material observed at the top of untreated, highway pavement soil subgrades. Alternative methods of preventing, or mitigating, the development of the soft layer are discussed.

Evidence is presented that shows that a soft layer of soil frequently develops at the top of untreated, highway soil subgrades. Data are presented that show strengths obtained from mechanical compaction are largely destroyed …