Precinct C is a multi-story commercial office development for the Australian Taxation Office in Canberra. A unique feature of the structural design for the project is the inclusion of with ‘Y’ shaped columns. The columns rise up from the multi-level basement carpark to the underside of the first floor, spitting in two at an angle of 50 degrees. The arms for the ‘Y’ are 6.2 m long and range in height from 1.2 m to 3.7 m above ground. The Y columns support the structure and therefore were a key component on the critical path.
Working in conjunction with Bovis Lend Lease, InfraBuild Construction Solutions reengineered the reinforcement for the ‘Y’ columns to enable them to be prefabricated. If the reinforcing steel had been tied conventionally it would have been very labour intensive, time consuming and presented a number of OH&S challenges, as steelfixers would have been required to work at heights above 5 m. The 72 reinforcing prefabricated cages for the arms, in the 36 ‘Y’ columns were prefabricated at InfraBuild Construction Solutions and delivered to site when required, allowing flexibility in the project’s schedule and minimising congestion. The finished components only had to be lifted and placed onto formwork once delivered, and within a short time the concrete was ready to pour.
“Given that we were able to place each arm in around half an hour compared to probably three days to have tied the steel conventionally, PREFAB saved us about 100 extra days on the construction program.”
Ben Symons, BLL Construction Manager
InfraBuild Construction Solutions also prefabricated more than 100 reinforcing cages for the bored piers, which support the perimeter of the site. Once delivered, the 14-metre long cages were joined on site and installed to depths of up to 32 m.
Bovis Lend Lease saved time, on-site labour and avoided significant challenges by adopting a prefab solution.
Article published on Thursday, 01 January 2015