Geotechnical Challenges and Innovative Solutions for the Hyundai Motor Group Metaplant America (HMGMA) in Georgia

This paper provides a detailed case study of the geotechnical challenges and innovative solutions implemented during the design and construction of the HMGMA facility, located near Savannah, Georgia, approximately 30 mi from the Atlantic coastline. The site’s geotechnical profile presented unique complexities: loose to medium-dense sands in the upper 30 ft, underlain by interbedded soft clays and sands to a depth of 60 to 70 ft, with dense sands below. These conditions necessitated innovative foundation solutions to meet the project’s demands. Augered cast-in-place (ACIP) piles—also known as Continuous Flight Auger (CFA) or Auger Pressure Grouted (APG) piles—served as the primary foundation system for the buildings, while rigid inclusions (RIs) were used for ground improvement to limit settlements in heavily loaded slab areas. Soil liquefaction emerged as a tricky issue during the design phase due to the site’s location, soil composition, and extremely tight schedule. This paper highlights the comprehensive geotechnical exploration program, the design innovations, and the construction strategies that enabled the successful delivery of this groundbreaking project at an unprecedented speed. The findings and lessons learned from this endeavor offer valuable insights for future large-scale industrial developments under similarly demanding conditions.