John F. Kennedy Airport Site Redevelopment: Tapertube Pile Foundation-PPT Presentation

PPT Presentation

Pdf Summary

The JFK Airport redevelopment included a 30-foot extension to Terminal 8’s Head House. The project used tapertube piles, a foundation system common at JFK because the site’s sandy soils provide strong frictional resistance. Site conditions were checked against earlier borings and a 2019 investigation. The profile includes sand fill, a soft peat and organic silty clay layer, and deep glacial sand; liquefiable sand was identified around the organic layer.<br /><br />The steel piles were 14 inches in diameter at the top and 8 inches at the tip, with a 0.375-inch wall thickness. Fifty-foot piles had an allowable axial capacity of 80 tons, while 40-foot piles had a capacity of 30 tons. The upper half of each pile was coated.<br /><br />Testing included dynamic analysis (PDA) on two sacrificial piles, re-striking after one hour and examining capacity gain after three weeks. One PDA-tested pile also underwent a static compression test. The static test results aligned well with calculations using the Nordlund method. Vibration readings remained below 0.3 inches per second, under the 2-inch-per-second limit, and no settlement was recorded.<br /><br />Construction required responses to low headroom, a broken hammer, underground obstructions, weld and splice cracks, and high blow counts in densified soil. Solutions included pile splicing, additional PDA testing, pre-augering the upper 10 feet, inspecting pile interiors with a camera, and driving additional piles at alternate locations. The project concluded that tapertube piles are an efficient foundation for JFK’s granular soils and emphasized the importance of locating obstructions and old foundations.

Keywords

JFK Airport

Terminal 8

tapertube piles

foundation system

sandy soils

dynamic analysis

static compression test

Nordlund method

liquefiable sand

pile splicing