Telegraph Road Pymble: Engineering on Sydney's North Shore

Telegraph Road Pymble

The Telegraph Road project in Pymble required innovative engineering solutions for a site with challenging topography and geology typical of Sydney's upper North Shore.

Site Challenges

The upper North Shore is characterised by steep terrain and variable geological conditions. The Telegraph Road site featured a significant fall across the property, which created both challenges and opportunities. The slope enabled the incorporation of basement parking without extensive excavation, but it also required careful management of geotechnical risks associated with excavating into sloped ground.

Geology

Pymble sits within the Hawkesbury Sandstone formation, which can vary significantly in quality over short distances. Our geotechnical investigation revealed zones of fractured rock and clay-filled joints that influenced the foundation design and excavation methodology.

Structural Design

The building was designed to step with the natural terrain, minimising the need for extensive cut and fill. This approach reduced construction costs and preserved the site's natural characteristics, which was important in the context of the surrounding neighbourhood.

Retaining Structures

The sloped site required engineered retaining walls along multiple boundaries. We designed a combination of reinforced concrete retaining walls and anchored shotcrete walls, selected based on the height to be retained and the proximity to boundaries. All retaining structures were designed for both long-term earth pressures and short-term construction loads.

Environmental Considerations

Working on Sydney's North Shore requires sensitivity to tree preservation and natural drainage patterns. Our civil design maintained natural overland flow paths and incorporated stormwater management measures that respected the site's environmental context.