Drilled-In Displacement Piles: Lessons Learned from Case History at JFK Airport in New York-Video

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The presentation reviewed the use of drilled displacement piles (DDPs) for Delta Airlines’ Terminal 4 redevelopment at JFK Airport. Site conditions included hydraulic fill over soft organic marsh deposits and dense glacial sands, with groundwater roughly 7–8 feet below grade. Because of access and overhead-clearance constraints, the team selected DDPs instead of micropiles, using a 3D ground model and pilot load testing to guide design.<br /><br />Compression, tension, and lateral tests confirmed the piles’ capacity, including a substantial contribution from base resistance in sand. Test results allowed the design length to be reduced from about 60 to 50 feet. For 178 production piles, acceptance criteria included minimum embedment, casing through the marsh deposits, installation torque, and grout volume. Field observations highlighted the value of continuous torque monitoring and flow meters for grout measurement; higher-capacity installation equipment could also reduce difficulty advancing through dense sand.<br /><br />The team concluded that DDPs can be a cost- and capacity-effective alternative to micropiles in suitable ground, provided rigorous testing and quality control are used.

Keywords

drilled displacement piles

Delta Airlines Terminal 4

JFK Airport redevelopment

pile load testing

ground model