McLachlan and Ann included a 12-level commercial office tower, a 22-level residential tower and a 4-level mixed use building with recreational landscaped deck.
ADG were engaged to deliver a value engineered solution as the development was in danger of extensive project delays due to the presence of strong rock in the project grounds, resulting in a lengthy excavation process.
Upon review of the construction program, it was suggested that slip form construction for the central lift and stair cores to the residential and commercial buildings would maintain original target dates, if the core structure was able to be accelerated. ADG re-engineered the core structures to cantilever free standing up to 22 levels unsupported, allowing the building structural works to commence whilst excavation work continued into the strong rock below ground.
ADG delivered an economical solution to keep work progressing and provided the client with a talking point in the market and giving the development’s pre-sales and leasing team a selling advantage.
A subsequent challenge was to mitigate the potential delay from when the cores were to be completed and the structural slab construction was to commence.
ADG carried out detailed finite element analysis of the core structures to analyse staging in order to minimise temporary works requirements. The cores were able to cantilever over 60m high from foundation level, while maintaining structural integrity of the wall and its foundation.