Lessons Learned in Applying Gravel Interference Corrections for Cone Penetration Test

For many critical sites in the dam engineering community, the liquefiable material of interest is a gravelly foundation alluvium soil or zone rich in gravels within the embankment dam itself. Many of the tools available to the geotechnical community have been developed based on sand or clay data, with extrapolation to gravelly materials. Specific to the Cone Penetration Test (CPT), new methods for correcting for gravel interference have been developed by the geotechnical engineering community in recent years. With an inventory of hundreds of structures with gravelly materials in the foundation or embankment that could be unstable in strong ground shaking, it is imperative for the US Bureau of Reclamation to have tools available to study these materials, their conditions, and impacts to the dam safety case. This paper presents a set of lessons learned from applying recently developed gravel corrections tools for CPT data to ten different sites across the central and western United States. These lessons learned are intended to help guide further investigations by academics while showing practitioners some of the nuances in applying gravel corrections for a range of geologic conditions.