Geotechnical Investigation of the Intertidal Zone in Duck, North Carolina, during Tropical Storm Melissa and DUNEX

Geotechnical data were collected throughout During Nearshore Event Experiment (DUNEX) at the US Army Corps of Engineers Field Research Facility (USACE-FRF) in Duck, North Carolina in October 2019. On October 10, tropical storm Melissa developed over the Atlantic and resulted in energetic wave conditions, storm surge, and wave collision at the dune near the USACE-FRF. In addition to measurements of beach sand moisture content, flow conditions just above the bed, and geomorphodynamics collected by DUNEX collaborators, geotechnical measurements included pore pressure monitoring within the upper meter of the beach sand in multiple cross-shore locations, tests of in-situ sediment strength using different penetrometers and vane shear devices, and scour monitoring at one pier pile. Furthermore, high quality sediment samples suitable for testing moisture contents and bulk density were collected at multiple subsequent days during low tide and when the beach sediment surface was accessible. The sediment samples enabled further geotechnical characterization of the beach sediments in the laboratory. This dataset demonstrates the significant and rapid spatiotemporal variations in geotechnical parameters, including soil fabric, sediment strength, and pore pressure behavior, at a sandy beach during storm conditions. Another key aspect is that the dataset was collected in coordination with other multidisciplinary data collections in the framework of DUNEX which will provide a unique insight into the correlation of different processes. It is expected that the multidisciplinary approach has the potential to reveal new information on beach erodibility during storm events.