“With the Brisbane City Hall Restoration, we were able to take the client on a journey and help them solve their problems in untraditional ways. Brisbane City Hall is a prime example of how 21st century tools and techniques can be used to breathe new life into historically significant buildings,” said Ralph Belperio, Built Environment Leader – Adelaide/Melbourne.
Constructed in the 1930’s, Brisbane City Hall is one of the iconic buildings of South East Queensland. The heritage-listed City Hall is seen by many as the heart of Brisbane and it has been the backdrop to many social, cultural and civic events over the decades. The building, however, was in dire need of refurbishment and it closed its doors at the end of 2009 so that it could undergo an AUD215 million restoration.
In 2010, Aurecon was engaged to assess the structural condition of the building as well as design the necessary remedial and strengthening works. Aurecon undertook a comprehensive testing regime to establish the physical properties of the concrete. During these initial assessments, the design team found concrete that was 80 years old at Brisbane City Hall and that this concrete was about one tenth of the strength of contemporary concrete. Our research failed to uncover any precedence worldwide for working with this type of material so the project team had to develop a new prototype of its own in order to find a solution for the refurbishment work that was needed.
Aurecon used analytical models to investigate different augmentation strategies and existing material options. A challenge that the team experienced was working with slabs that were exposed in the building fit out, which made traditional methods of augmentation difficult in the heritage context of the building. To overcome this, Aurecon developed an analysis approach incorporating strengthening overlays using concrete theory derived from codes of practice worldwide, validated by finite element models and by full scale load testing on site. This resulted in solutions which left the soffit of the slabs largely untouched.
The project targeted a 4 Star Green Star Public Building v1 rating using the pilot programme developed by the Green Building Council of Australia. Design initiatives that were used to achieve this included focusing on retaining the existing structure and limiting the amount of new materials that were used in the construction.
By using 21st century tools and technology, the team found a way to strengthen the structure so that the life of the building will be extended by at least another 80 years. The restoration project, which was completed in 2013, has re-birthed this iconic public facility into an outstanding, updated building that houses state-of-the-art technology, an auditorium, performing spaces, offices as well as a new Museum of Brisbane in a contemporary structure atop the roof. The building is future-proofed for the next generations and the refurbishment has also vastly improved the building’s energy consumption. The result of this project was the client seeing Aurecon as a trusted advisor and has already started to engage the company’s services for future projects.