As part of a marina development to complement the boat harbour at Exmouth, near the North-West Cape of Western Australia, Landcorp commissioned the design of a 92-metre long landmark footbridge over the main canal. The footbridge provides a pedestrian link between the resort and harbour facilities and surrounding residential and commercial developments nearby the main marina precinct.
BG&E provided the structural design concept for the footbridge, with input from Jones Coulter Young Construction, as well as provided a practical solution for fabrication and erection.
In addressing the design issues for the high steel arch, the design was proportioned with curved surfaces, slender arch members and shallow deck. Slenderness was achieved principally by triangulating the hangers. It was assessed for aesthetics and structural economy, the height of the arch above the deck should be about twice the height of the deck above the water and that cables should be set at about 45 degrees of inclination. Thus, resulted in cables crossing over each other contributing to the shear stiffness of the structure.
Our team also provided construction support and management for the stability of the arch during temporary staging of the erection, and during lifting and transferring of the precast deck units into position.
The scope of works also included designing the positioning of the crane outriggers close to abutment walls for the major lifts of steel arch, precast deck units and the adjustment of the inclined cable lengths at rigging screws, as was required for alignment and profile of the deck.
Exmouth is one of the State’s premier tourism destinations.