Moving the Cape Hatteras light station - Geotechnical considerations

Relocation of the Cape Hatteras Lighthouse and associated structures across a coastal dune system was planned by the National Park Service to protect the structures from continuing coastal erosion. The lighthouse is a masonry structure about 61m tall and weighing about 4,400 metric tons. The contractor performing the relocation used a system of steel beams laid over steel matting on a prepared ground surface to support the structure during the move. A geotechnical site characterization program consisting of conventional exploratory borings supplemented by dilatometer testing and a large scale area load test was performed to determine the necessary ground improvement. Elastic analyses were performed to estimate settlements under the planned move system. Measurements of the deflections of the steel mats during the move were obtained.