Field investigation of engineering properties and uniformity of subgrades chemically treated with LKD

Abstract

A field investigation was performed immediately after the construction of a subgrade treated with 5% lime kiln dust (LKD) to determine the degree of uniformity and quality achieved using current construction techniques. A 280-m long section of a road was chosen for the field tests. The first 140 m was treated with LKD over a target thickness of 41 cm (16 inches), which is the current standard practice in Indiana. The second 140 m was treated with a reduced target thickness of 36-cm (14 inches). For the thicker, 41-cm treated subgrade, the increase in california bearing ratio (CBR) with respect to that of the untreated soil at the site was around 100%, as average, while for the thinner, 36-cm treated subgrade it was about 350%. All field and laboratory test results showed consistently better and more uniform results for the 36-cm thick treated subgrade than for the 41-cm thick treated subgrade.

Keywords:

• DCP
• engineering properties
• LKD
• subgrade
• uniformity

Acknowledgements

The work presented was supported by the Joint Transportation Research Programme administered by the Indiana Department of Transportation and Purdue University. The contents of this paper reflect the views of the authors, who are responsible for the facts and the accuracy of the data presented herein, and do not necessarily reflect the official views or policies of the Federal Highway Administration and the Indiana Department of Transportation, nor do the contents constitute a standard, specification or regulation. The authors are grateful to the Federal Highway Administration/Indiana Department of Transportation/Joint Transportation Research Project for supporting this research.