SuperPile 2017 Online Proceedings, (DFI)
Optimizing the Design of Driven Pile Foundations with Instrumented Static Load Tests
Peter Narsavage, P.E.
Two large bridges over the Great Miami River in Dayton, Ohio, were recently constructed. The foundations for these bridges consist of driven piles, and the foundation design was optimized for the least cost given the constraints of the site conditions and pile drivability. Over 40 different possible combinations of pile diameter, pile wall thickness, pile capacity, and pile hammer were considered during design, including open ended piles. Cost factors included material costs for steel and concrete including length surcharges over 50 ft, crew and equipment time and costs to unload and drive the piles, and time and material costs for splices. Foundation costs were compared on cost/ton basis. The selected pile design was a 16-inch pipe pile with a nominal resistance of 600 kips, which exceeded the state DOT's standard maximum nominal resistance of 450 kips for this size pile. During construction, two instrumented static load tests and many dynamic load tests (PDA with CAPWAP) were performed to evaluate the selected foundation design and the results used to further refine the foundation design.
|article #2695; publication #1031 (SP-2017)|