Determination of USCS from USDA Soil Classification for Vehicle Impact Quantification.

From an agronomic perspective, the US Department of Agriculture (USDA) soil classification system is the most widely used and reference system in the United States.  The Universal Soil Classification System (USCS) system is more widely used for design and construction activities and also widely used to determine placidity levels used for maneuverability and physical erosion management techniques.  Translating USDA soil classification to USCS schema is often fraught with error and uncertainty.  Most US soils have solid USDA surveys, but do not have USCS.  The Army’s Engineer Research and Development Center, Construction Engineering Research Laboratory (ERDC-CERL) developed a method to rapidly determine USCS from USDA to soils data for use in Vehicle Impact Models (VIMs).  This method was used to calculate rating cone index (RCI) for each soil map unit, on over 70 installations, across a range of soil moistures on a monthly time scale to determine soil resiliency to vehicle impacts.  This paper will discuss the methodology used to convert USDA classification to USCS classification as well as the development of soil resiliency ratings.