Continental Towers is an existing 910,000 square foot office complex comprised of three 12-story towers connected to a central commercium. Renovations to the complex began in 2015 and included a new entrance canopy, new parking garage, new connector walkways between the garage and existing towers along with various upgrades to the building facades, interiors and landscaping. The new four-story precast concrete parking garage was to be located above an existing detention pond.

The primary engineering scope of work included the structural design of the caisson and grade beam foundation system for the garage. The above-grade precast concrete garage was designed by others. Other miscellaneous tasks included the structural design of the two steel-framed connector walkway buildings, wood smoking vestibule and mat foundation system for the new entrance canopy. K&H also provided engineering consultation for various plaza elements, bollards and stairs.

Services included structural analysis and design, development of construction documents, review of shop drawings and assisting the Architect in responding to requests for information (RFI’s). Multiple revisions to the garage foundation and connector walkways were required throughout the project. Different approaches were explored to maintain aesthetics of the garage by burying the exterior caisson caps below the sloping grade. Since the garage was built atop a detention pond, the interior caissons were designed as unbraced and exposed above the pond floor and the grade beams were designed to retain the strong hydrostatic loads from the exterior perimeter soil. K&H was instrumental in thoughtfully adjusting the garage design to meet the aesthetic requirements of the architect, loading requirements of the precast structure itself and the site restraints caused by the detention pond and poor soil capacity.