Design-Build Driven Pile Foundations: Optimizing Pile Efficiency-PPT Presentation

PPT Presentation

Pdf Summary

The presentation describes the design and construction of driven-pile foundations for two heavily loaded buildings, requiring 1,197 piles and approximately 205,000 linear feet of 12-inch steel pipe. The project used a compact pile size to address downdrag concerns, with concrete fill providing additional structural capacity.<br /><br />The site’s thick, soft clay layer over dense clayey sand offered potential for soil setup to increase pile resistance over time. Because the required test load exceeded the capacity that could be demonstrated in unfilled steel piles, the team tested concrete-filled piles and incorporated setup into the geotechnical design.<br /><br />Initial testing plans relied on steel-pile restrikes and a time-setup curve to estimate production-pile capacity. Results showed that steel restrike penetration resistance was highly variable and did not reliably predict the much higher capacity measured in concrete-filled piles. The team therefore switched to restriking concrete-filled production piles. These tests confirmed increased skin friction and end bearing, while concrete fill also raised pile impedance and stiffness—reducing pile movement but making further driving more difficult.<br /><br />Hammer trials led to D30 hammers for production driving and D46 hammers for testing. The project highlights the value of early coordination among the contractor, engineer, and supplier; constructability-focused design; composite piles; soil setup; and field testing to validate assumptions. The work was completed on schedule and under budget, with 20,500 labor hours and no lost-time incidents.

Keywords

driven-pile foundations

concrete-filled piles

steel pipe piles

soil setup

downdrag

skin friction

end bearing

pile testing

constructability

composite piles