Specialist geotechnical and foundation engineering support for one of Australia’s largest solar farms, where innovative foundation redesign, testing and construction advice significantly improved pile installation productivity across a 200-hectare renewable energy development.
Client
Downer for ESCO Pacific
Location
Townsville, Queensland
Sector
Energy Renewables & Utilities
Services Delivered
Construction SupportFoundation ReviewPile DesignPile VerificationSign-OffStatic Pile Testing
The challenge.
The Ross River Solar Farm involved the installation of more than 62,000 driven steel piles to support photovoltaic tracker systems across a 200-hectare site near Townsville. Ground conditions comprised very stiff to hard silty clays interbedded with dense clayey sands, resulting in highly variable pile driving conditions across the development. The piled foundations were initially designed by others. When construction commenced, installation difficulties were encountered, creating significant impacts on productivity and programme certainty. The project required a practical, data-driven solution that could improve constructability while maintaining the required structural and geotechnical performance.
The approach.
FSG was engaged to review the foundation design, assess the causes of pile refusal and identify opportunities to improve installation efficiency. A targeted programme of pile testing and geotechnical assessment was undertaken across the site, supported by detailed analysis of installation data and ground conditions. Using the results of this investigation, FSG redesigned the foundation system and demonstrated that significantly shorter piles could achieve the required performance criteria. Areas with differing ground behaviour were identified using statistical analysis, allowing installation methodologies to be tailored to site conditions and alternative construction approaches, such as pre-boring, to be adopted where required. FSG remained closely involved throughout construction, providing ongoing technical advice, validation testing and pile verification services.
The outcome.
The revised foundation solution substantially improved constructability and resolved the widespread pile installation issues encountered during the early stages of the project. By reducing pile lengths, refining installation methodologies and providing a robust verification framework, FSG helped the project team significantly increase installation productivity while maintaining compliance with the design requirements. The collaborative approach enabled informed decision-making throughout construction and delivered a practical, best-for-project outcome. Client feedback indicated that daily installation productivity increased by over 40 times compared with the original construction approach, contributing to the successful delivery of this major renewable energy project.