Seymour White Smithbridge JV & KBR
Pile Testing and Certification Constructability Review
Design and Analysis of Deep and Shallow Foundations
The Townsville Port Inner Harbour Expansion Project (TPIX) involves the upgrade of a series of existing wharf berths, incorporating the installation of around 200 No. driven steel tube piles for wharf structures as well as bored piles and shallow foundations for associated buildings and infrastructure. FSG has provided a range of design, constructability, testing and verification services to contractor, Seymour White Smithbridge JV (SWSJV) and designer KBR in relation to a range of foundation related challenges.
Site Geology and Challenges
The geotechnical conditions at TPIX consist of variable depths of uncontrolled filling overlying marine sediments and variable depths of weathered granite rock, with granite bedrock becoming high to very high strength very abruptly. The depth to the hard granite varies significantly across the project and impacts heavily on the ability to achieve the required penetrations for tension loading. Major challenges on the project include, piling through uncontrolled fill, sign-off of heavily loaded piles in highly variable conditions, and achieving tension requirements without the need for expensive anchoring into high strength granite rock.
Scope of work
FSG took over pile testing and certification on the project after initial arrangements proved to be a major impediment to piling progress, and developed systematic and streamlined verification and sign-off processes. In response to the contractors concerns about the intial design requiring large diameter rock sockets into high strength granite, FSG developed an approach to optimise the assessment of pile tension resistances without anchor installation and also developed a lower cost design contingency for small diameter rock anchors if required. All rock anchors were elimated from the final as-built solution, realising significant cost and time savings. FSG also undertook design and certification of piling and shallow foundations for a range of other associated structures and buildings.
In response to client concerns, FSG optimised foundation design and verification processes to enable efficient pile construction and sign-off in complex and difficult ground conditions. Significant cost savings and program benefits were realised.