Foundation Design for the Elevated Station

Berry, Dennis L.; Braun, Forrest T.; ,

Foundation Design for the Elevated Station

by Dennis L. Berry, P.E., (M.ASCE), Pres.; BBFM Engrs., Anchorage, AK,
Forrest T. Braun, P.E., (M.ASCE), Vice Pres.; BBFM Engrs., Anchorage, AK,

Serial Information: Civil Engineering—ASCE, 2000, Vol. 70, Issue 12, Pg. 42-45,73

Document Type: Feature article

Abstract:

The Amundsen-Scott South Pole Station is located at an elevation of 2,850 m on the 3,200 m thick polar plateau, a field of ice and snow that is moving toward the ocean at a rate of 10 m per year. Since the snow continuously accummlates and never melts, the elevated station must be jacked up during its lifetime to accommodate the increasing snow level around it. The foundation system used comprises a series of 710 mm high by 610 mm wide steel box girders acting as foundation-grade beams between the foundation columns from which the 910 mm diameter foundation columns are cantilevered. To keep the snow bearing pressures uniform, the footing is wider where the bearing load per meter is greater. The wider footing is made up of 90 by 140 mm timbers on edge with plywood top and bottom. As design developed, the long-term bearing pressure on the snow was determined to be 34 kPa as established by the grade beam with the least vertical loads. All of the foundation columns are outside of the building envelope to allow the addition of column extensions for jacking. At the beveled leading edge of each pod the foundation columns are outside of the first level but underneath the second level. The design was based on jacking twice, a full floor height of 3.7 m each time.

Return to search