Logan Aluminum, Inc. (LAI) had plans to expand several production lines at its Logan County, Kentucky, facility and the work had to be completed under strict time schedules while the facility was still in operation. AEI provided surveying, geotechnical, electrical resistivity imaging (ERI) and testing, and inspection support on a variety of interrelated projects including the Hot Mill Building Expansion, the Cold Mill 4 East Expansion, and the SL4 Expansion. AEI also provided civil solutions for a gravel parking lot complete with improved drainage and settling basin to capture area runoff for water quality protection.
At the Cold Mill 4 Expansion, karst terrain was encountered where the Haney Limestone Member of the Golconda Formation contacts the Hardinsburg Sandstone. At this contact and to the east, limestone was encountered at auger refusal. To the west the limestone was not present resulting in shale or sandstone at auger refusal depths. Utilizing ERI, AEI was able to map the contact between the formations aiding in defining the area of karst concern. A targeted boring plan was developed to evaluate the physical extents of the karst features.
Due to the karst terrain and heavy structural loads, a deep foundation was needed. In lieu of a more traditional drilled shaft or H-pile deep foundation system, the Design/Build team elected to use large diameter Continuous Flight Auger (CFA) cast piles bearing on or in bedrock. The CFAs were 18 to 24 inches to over 55 foot in depth with a full rebar cage, like that of a drilled shaft, extending to the end of the pile.
AEI also supported Barge Design Solutions at the facility by providing surveying, Ground Penetrating Radar (GPR), and geotechnical investigation for the North Ingot Storage Lot. This lot utilized rail to store ingots designed at 15-20 kips per foot (klf) and 3 kips per square foot (ksf). AEI’s support at the LAI facility was a milestone achievement in our repertoire of supporting large, dynamic industrial facilities.