LUXURY INNER CITY PROJECT LEVERAGES PRECAST

3D PRECAST SOLUTION DELIVERS ARCHITECTURAL VISION
With precast concrete taking the spotlight within The Alex’s architectural vision, National Precast member Hanson Precast was approached to explore what could be achieved using the versatile product.

The project specifics were intricate and complex. The design of the three-dimensional panels that make up the building’s geometrical façade posed a challenge, as three of the four panel corners were not at right angles. However, the precaster provided an intelligent solution that hinged on 3D software and ultimately awarded them the contract to manufacture 240 precast concrete panels.

Each panel had a 3D profile, and Hanson Senior Drafter, Ben Peers, says that it was with the 3D software and models that they were able to develop the precast solution.

“Being able to model a structure in three dimensions allows us to almost ‘pre-build’ the building, iron out any problems at the outset, and from there, identify the optimal mould design,” he explains.

“The 3D drafting process is critical for a project of this nature.”

“Being able to model a structure in three dimensions allows us to almost ‘pre-build’ the building, iron out any problems at the outset, and from there identify the optimal mould design.” Hanson Senior Drafter, Ben Peers.

MINIMISING MOULD COST
Despite the geometrical façade’s complex appearance, Hanson’s Project Engineer, Robert Aldrich says that with clever planning, its construction was relatively simple.

“The secret was in developing the façade layout so identical panels could be placed at various locations on each elevation, therefore reducing the number of panel types required.”

Hanson was then able to design three versatile moulds to manufacture all the precast concrete panels.
“Shutters were designed to enable the myriad different combinations of sloped and straight edges, toothed panels, and different panel sizes to be accommodated.”

“Smart planning and our mould fabrication skills allowed us to minimise the mould costs for the project.”

Crisp aesthetic: The Alex demonstrates the possibilities furnished by early collaboration between architect and precaster.

PAINTED OFF-FORM PANELS FORM WINDOW OPENINGS
Each of the 240 panels adopted a Class 2 off-form finish and was then coated with a low-build white paint. The off-form panels offer a crisp aesthetic while also forming the building’s window openings. The load bearing design of the precast concrete allows each panel to have a positive connection with the suspended concrete floor at each level and therefore enables the panels to be stacked on top of one another to form the window openings.

INSTALLATION CHALLENGES OFFSET BY OFFSET BY REWARDS
The construction restriction of the tight inner-city site meant that a tower crane was required and specific transport frames were designed to accommodate the unusually-shaped panels, Aldrich confirms. These were delivered in their as-installed orientation and significant time was saved on site as there were no offloading or turning requirements.

“This project is a great example of what can happen when the architect and precaster work together from early on to plan and innovate for an excellent result.”

PROJECT: THE ALEX APARTMENTS
LOCATION: ALEXANDRIA, NSW
PRECASTER: HANSON PRECAST
BUILDER: NEWTOWN CONSTRUCTIONS
ARCHITECT: PROJECT SERVICES
ENGINEER: LMW DESIGN GROUP■