Waterfront Precinct Project, Eagle street pier, Brisbane

The Waterfront Precinct Project at Eagle Street Pier, Brisbane, is a landmark development requiring extensive ground engineering. The site, characterized by marine clays extending to 17m depth followed by stiff clays, required a sophisticated approach to support heavy piling equipment and deep excavation stability.

We deployed a comprehensive ground improvement strategy: Mass Soil Mixing (MSM) and Deep Soil Mixing (DSM). MSM was utilized to construct a stable platform for piling rigs and act as a structural strut for the combi-wall system. DSM was specifically employed to ensure stability for the D-wall trenching along the combi-wall alignment.

The project involved a massive scale of works, totaling 30,000 m³ of MSM and 20,000 m³ of DSM, requiring the consumption of 5,000 tons of cement. Execution was supported by two dedicated MSM rigs, a specialized DSM rig, and a high-capacity on-site batch plant with dual silos. The DSM columns reached diameters of 2.2m and depths of up to 19m.

The site was highly congested with significant subsurface obstructions, including heritage items, which caused substantial wear and tear on equipment. We resolved this through systematic excavation and documentation of all obstructions via GPS tracking. Furthermore, the congested site environment was managed through disciplined site coordination, ensuring seamless integration between DGSA's works and other concurrent trade activities.

Both MSM and DSM activities were successfully completed, providing the robust ground conditions required for the project’s critical infrastructure. Despite the high equipment density and site constraints, the project met all quality specifications, enabling the main construction phase to proceed on schedule.