Abstract:
Deep foundations were required for repairing and replacing an existing concrete slab floor that was failing inside the United Air Cargo Facility in Newark, New Jersey. The project was divided into multiple phases allowing the cargo facility to continue operating on a twenty-four hours a day and seven days a week schedule. It was crucial that the facility remained operational during construction. The new construction was located inside the existing warehouse with low headroom conditions. The equipment required to install helical piles had to be low emission producing and able to fit through loading dock doors. Helical piles were ideal because it offered a small and simple footprint during production. They also produce little to no spoils, minimal noise, and minimal vibration, making it an appropriate solution for working within an operating facility, especially when the geological conditions and applied loading are amenable to the use of helical piles . Depending on duration between phases, equipment was either left onsite or
completely demobilized. Overall, the equipment required for helical piles is minimal, so it kept
the cost down for re-mobilization in a multi-phase project.
Installation depths were 30'-33' before reaching the required torque. The concrete contractor
had minimal cleanup and footing setup prior to pouring the new concrete slab. Buried within the
concrete slab were numerous and randomly crossing electrical conduits. Helical piles allowed
the installation to be extremely close to these exposed conduits without disturbance or damage.
Helical piles are ideal for quick mobilization and low equipment costs but are limited with the soil
conditions and their lack of ability to drill through hard obstructions.