Installation of 1.2m Diameter Closed-Ended Steel Tubular Piles into Kings Park Formation
SourceClosed-ended driven steel tubular piles up to 1.2 m in diameter have been installed to support pier and abutment structures for a pedestrian bridge over the Swan River in Perth, Australia. Keller was engaged as the specialist piling contractor for the installation of the closed-ended tubular piles. Piles were driven through medium dense to dense sand and stiff clay layers into the Kings Park Formation. A reinforced concrete infill was then constructed after the pile was driven to the design depth. During the tender phase, extensive wave equation driveability analyses were performed by various parties in order to provide the best assessment on the adequacy and performance of the driving hammer selected for the installation of the 36-m long pile. Dynamic load testing, with CAPWAP signal matching, was performed in conjunction with partial driving monitoring to manage the stresses in the pile and the capacity during installation. Full driving logs, final sets, and temporary compressions were recorded for all production piles as part of quality assurance requirements. This paper presents a summary of the driveability analyses performed, the installation of the piles, discussions on the performance of driveability analyses, and the challenges encountered in the driveability analyses of large-diameter closed-ended piles. The paper also presents the processes and results of the refined wave equation analysis that has provided a more reliable driving prediction. The use of the Pile Driving Monitor to verify the pile capacities of the contract piles is also discussed.