Evaluation of Pile Setup Phenomenon for Driven Piles in Alabama: Fid-Bau Portal

Evaluation of Pile Setup Phenomenon for Driven Piles in Alabama

Haque, Md. Nafiul / Steward, Eric J.

Pile setup is defined as increase of pile capacity with time after the end of initial driving (EOID). Construction costs can be significantly reduced by the incorporation of pile setup in design phase of piles, and has recently been included in the design phase by various states. This study was performed in Alabama, to investigate the pile setup phenomenon for driven piles (i.e., HP pile and PPC pile). The size and geometry of the pile contribute to the amount of setup differently. Load test data was acquired from the Alabama Department of Transportation (ALDOT) of 18 test piles (7 HP piles and 11 PPC piles) driven throughout the region. All the test piles showed a significant amount of setup after EOID. All restrike data were analyzed using signal matching programs CAPWAP and iCAP; and were compared to the PDA in order to analyze setup behavior. The results indicate that setup developed on all test piles (7 H-piles and 11 PPC piles). Logarithmic setup parameter “A” for Skov and Denver (1988) model was back-calculated for these 18 piles. The results showed that the average value of “A” parameter was 0.21. However, the “A” parameter was higher for HP piles compared to PPC piles. The iCAP results indicate that the total axial pile capacity (regardless of pile type or size) increased over time from EOID (setup) by an average of 70% regardless of the soils encountered.