Abstract:
Drilled-In Displacement Piles (DDPs) present several advantages over other deep foundation solutions that make them an excellent solution for challenging conditions such as those encountered at the John F. Kennedy (JFK) International Airport Headhouse Expansion Project. For one the low-headroom restrictions required the installation to occur under railway tracks with as little as 12 feet of clearance. Secondly, their ease of installation and overall material requirements deemed them more competitive than traditional micropiles from both schedule and cost point of view. Lastly, the low vibrations induced by these DPPs to the surrounding sensitive structures of an operational airport, contributed to the final decision of recommending this foundation system for the Project. This paper documents the use of the DDPs and the approval process associated with the Authority Having Jurisdiction from a case history perspective