Constructing a 957 bed 13-story tower in the center of the Duke University Hospital campus required significant excavation shoring closely coordinated with the myriad existing below grade utilities.   Skanska hired Subsurface to design and install the ground shoring system.  Subsurface proposed an anchored soldier pile wall to reduce the number of horizontal shoring elements that could conflict with existing utilities.  The soldier piles were installed in pre-drilled holes and back filled with concrete. The holes were drilled using a Bauer foundation drill rig.  Drilling to install soldier piles eliminates vibration and reduces noise versus driving piles into place.  The anchors were attached to the wall using walers to allow for accurate anchor layout and in-field adjustments to avoid existing utilities.

Skanska, Calyx and the Duke Risk Mitigation team created a 3-D model of the proposed anchored soldier pile wall and existing utilities.  TJ Ju, PE, Design Engineer along with Alex Smith, PE, Division Manager and Ben Possiel PE, Project Manager worked with Skanska and Calyx through multiple iterations of design in order to develop a shoring plan that would retain the deep cut while reducing the risk of utility damage.

Kelly Williams, Superintendent, used his 30 years of construction experience to install the shoring system, coordinate deliveries in the midst of an active hospital campus, and work closely with Skanska to complete the excavation shoring construction safely and on time.

• Use of 3-D modeling by Skanska, Calyx Engineers, and Duke Risk Mitigation to avoid utilities
• 22,000 sf Anchored Soldier Pile Wall

• Skanska
• Duke Health
• Duke Risk Mitigation Team