Test Pile Programs at Chicagoâ€™s Navy Pier-PPT Presentation

PPT Presentation

Pdf Summary

The presentation reviews two test-pile programs associated with Navy Pier projects in Chicago. During the 1992 dock expansion, 12.75-inch pipe piles were driven to hardpan with a target ultimate capacity of 400 kips. Twelve piles were dynamically tested, with restrikes 15–30 days after driving; four also received static compression and tension tests.<br /><br />For the later Flyover Phase II project, congestion influenced the construction approach. Five HP 10×42 test piles were dynamically tested, including short- and long-term restrikes at 1 and 30 days. One pile received a static load test. End-of-drive capacities were 47–58 kips. Friction setup factors ranged from 1.6–2.3 at short-term restrike and 2.4–3.3 at long-term restrike. The static test indicated a capacity of 115 kips using the Davisson offset and 120 kips under the City of Chicago settlement criterion. Final reported capacities included 120 kips by both PDA and static testing, with other PDA results of 120, 150, and 160 kips.<br /><br />The presentation compares static testing, dynamic testing, and capacity estimates from formulas and wave-equation analyses. Its main recommendations are to select dynamic formulas suited to the pile and soil conditions, use wave-equation analysis to improve on basic dynamic formulas, plan load-test programs around target depths and capacities, and account for soil setup—which may allow shorter piles and reduced driving time.

Keywords

Navy Pier

test piles

dynamic testing

static load test

pile capacity

friction setup

wave-equation analysis

dock expansion

Chicago

pile driving