Structural engineering for iconic projects
The Archibald - Gosford
Project Overview
The development consists of two high-rise towers built upon a shared multi-level podium.
- Total Height: 28 storeys (East Tower) and 27 storeys (West Tower).
- Composition: The structure consists of 2 towers with common podium, 28 storey high rises with roof and 1 basement level,130 hotel rooms, 323 residential apartments, Ground floor Pub + Hotel Lobby + Retail, Hotel foyer at Level 01, and a striking 960 m² rooftop “Skybar.”
- Key Stakeholders: Developed and built by ALAND; Architecture by Dickson Rothschild (Concept) and Place Studio (Delivery); Structural Engineering by JSBC Consulting.
Architectural Form
The architectural language is a tribute to the local geography, specifically the sailing culture of the nearby Brisbane Water.
- Form & Massing: The towers feature striking white, sail-like curves. This “coastal luxury” aesthetic is achieved through articulated precast concrete and energy-efficient glazing.
- Facade Treatment: A monochrome motif is softened by vertical greenery and external plantings integrated into the balcony systems. The use of floor-to-ceiling windows, maximizes natural light and views.
- Public Domain Integration: The ground floor acts as a “vertical village,” featuring a large pub and retail precinct designed to draw pedestrian traffic from Donnison and Mann Streets, integrating the private development with Gosford’s urban fabric.
Engineering The Archibald: Our Structural Solutions
As the lead consulting structural engineers for The Archibald in Gosford, NSW, JSBC Consulting was tasked with delivering the structural framework for this landmark twin-tower development. From navigating complex waterfront ground conditions to optimizing high-rise load paths, our team engineered practical, high-performance solutions to bring this architectural vision to life.
Below is a snapshot of some of our notable structural engineering solutions on this flagship project:
1. Overcoming Waterfront Challenges: Specialized Foundation Design The site’s proximity to Brisbane Water and a high water table necessitated a highly specialized foundation approach. Rather than relying on a standard basement design, JSBC Consulting engineered a Raft Slab on Piles to actively address significant hydrostatic (uplift) pressure and poor soil stability.
- Hydrostatic Resistance: We designed a reinforced concrete raft—reaching thicknesses up to 1.5 meters thick under cores —to provide the necessary dead weight to effectively counter buoyancy.
- Tension Piling: We engineered deep piles designed to work in tension. These piles effectively “pin” the raft to the underlying Hawkesbury sandstone bedrock, preventing the massive structure from lifting as groundwater levels press upwards.
2. Bridging the Gap: The Post-Tensioned Transfer Slab: At the heart of The Archibald’s structural integrity lies a masterfully engineered transfer slab, designed by our team to bridge the gap between two entirely distinct architectural layouts: the residential towers above and the open commercial and car parking zones below.
The Structural “Bridge”: Our engineering team implemented a high-strength, post-tensioned transfer level. This massive horizontal element captures the immense vertical loads descending from the 28-storey residential towers and redistributes them seamlessly into the podium’s reinforced column network.
