Keller has said that it is close to completing work on a major piling project in Osborne near Adelaide in Australia that will help deliver the nation’s next generation of naval vessels.
Working for main contractor Lend Lease, Keller is installing 2,000 traditional driven cast-in-situ piles (Frankipiles) and 2,500 driven precast concrete piles to support the large concrete platforms for the development.
The investment in expanding the Osborne naval shipbuilding precinct is part of a AUS$1bn (£568M) project by the Australian government and the future frigate programme at Osborne is one of the largest projects within the scheme.
Keller first worked at the site in 2008 using Frankipiles for an adjacent platform which helped secure the current project.
“The main contractor Lend Lease – who we’ve worked for many times – needed a foundations contractor with experience in this part of Adelaide, who could deliver a design-and-construct project, meet the strict pile-performance criteria and meet what is a fast-tracked programme,” said Keller engineering manager Ken Wright.
“From a technical point of view, the pile loads are relatively high, settlement performance criteria are stringent and the buildings are going to be situated close to the Port Adelaide River where the top 10m of soil is weak. The project required a piling solution which provided a superior performance and also minimised spoil generation across the project site. A Frankipile pile solution was chosen not only because of its superior performance but also because it’s a spoil-free solution, which reduced project costs and risks associated with spoil generation and handling on the project.
“Due to programme constraints and limited local plant resource, we explored a number of alternative design solutions for the more lightly loaded piles. These included driven precast, rigid inclusions and continuous flight auger piles to supplement the Frankipiles and give our client confidence that we would meet their schedule.”
The contract was awarded in December 2017 and work started on site in March this year.
The project required an extensive testing regime, including full-scale static compression load tests, static lateral load tests, dynamic pile testing and integrity testing to ensure the piles would perform as intended.
“We’ve also taken the opportunity to perform some additional testing, adding strain gauges on the base and shaft of several test piles, which will help us refine and improve our pile designs for future projects,” said Wright.
Keller has been using five piling rigs to deliver the work and set up a pile casting facility on site to produce around 600m of pile segments each day in order to keep the project on track.
Work is now nearing completion.