Solving the engineering problems posed by the Parliament Square development site has resulted in a Tasmanian first for the flagship project.
The dramatic Y columns at the Salamanca Building rise 14m and reach more than four storeys and allow the building to cantilever over a 130-year-old sandstone retaining wall, support a multi-level office complex and form a centrepiece for the building’s lobby.
Each taking 3 weeks to build, the refined shapes were extremely challenging, not only in design but also in construction. With no second chances, each column required 100% perfection.
Reinforcement cages were prefabricated off site with two prototype pours conducted in order to test the complexities, processes and selections ahead of undertaking the first column on site. Concrete placement, tolerances, form profile, vibration and stripping time were all key items tested as part of the offsite process.
Acting as the buildings bold structural elements, the columns required special formwork, the highest strength concrete used in a Tasmanian building project, custom made reinforcing cages, laser cut templates and more than 400 tie bars at each column yoke.
With the slight sloping of the columns arms, a special cradle was constructed to support the concrete pump line allowing the concrete delivery line to be gently withdrawn as the concrete rose within the form.
Designed with an “off form” finish there were no second chances.