Tonkin Gap Northern Dive Structure – Diaphragm Walls

The Tonkin Gap project, specifically the Northern Drive structure, is a crucial infrastructure development aimed at improving traffic flow and reducing congestion in Perth’s northeastern corridor. This project is part of a broader initiative to upgrade Tonkin Highway between Collier Road and Dunreath Drive, addressing one of the most significant bottlenecks in the region.

The Northern Drive structure component involves the construction of new bridges, underpasses, and associated roadworks to enhance connectivity and accessibility. Key features include widening the highway, constructing additional lanes, and creating new interchanges to facilitate smoother traffic movement. This part of the project also includes extensive earthworks, drainage improvements, and the installation of noise barriers to mitigate the impact on surrounding residential areas.

The Northern Drive structure is designed to accommodate future transport needs, with provisions for both road and rail infrastructure, including the Morley-Ellenbrook Line, which is part of the Metronet expansion. This integration aims to promote multi-modal transport options, reducing reliance on cars and encouraging the use of public transportation.

GFWA’s scope of works for the project included the supply and installation of a diaphragm wall (D-wall) comprising 98 panels. Each panel was 800mm thick, with depths ranging from 8 to 26 meters, totalling an area of 10,970 square meters. This D-wall installation was crucial for providing structural support and soil retention, particularly in areas with challenging geotechnical conditions. The panels were installed to ensure stability and integrity, addressing the project’s demands for a robust and reliable underground barrier. GFWA’s expertise in deep foundation solutions ensured the successful execution of this complex and critical component of the construction project.