Liberty Industrial carried out the deconstruction of the landmark Sydney Harbour Control Tower for Barangaroo Delivery Authority. The works formed part of Sydney’s multi-billion dollar Barangaroo Precinct Development Project.
The project involved the deconstruction of an 87-metre high redundant harbour control tower consisting of a reinforced concrete column topped by a stainless steel and glass observation and operations room.
The tower was situated in Sydney’s newest headland park, Barangaroo Reserve. The base of the tower stood in the Cutaway, a huge underground cultural space under the headland, and rose through a void above the headland park. The removal of the tower is part of the overall vision for Barangaroo Reserve, which is to restore a naturalistic look for the headland following a century of industrial use.
Barangaroo Delivery Authority appointed Liberty Industrial to remove the Harbour Control Tower following the proposal of an innovative and carefully considered deconstruction method designed to minimise the impact on local residents, businesses and visitors to the Headland Park where the tower is situated. Liberty Industrial’s proposed method also enabled continued use of the below ground event space where the base of the tower is situated.
The original design solution suggested by the client within the request for tender was relying on classic urban demolition techniques such as scaffolding protection, heavy crane lifts or concrete sawing, which would have caused major disruption to the surrounding community.
Mindful that the site is situated in extremely close proximity to a residential area with many heritage-listed buildings and is in the middle of a public space, Liberty Industrial proposed an alternative methodology designed to limit the footprint of the site and minimise disruption to local residents and visitors.
Liberty proposed a deconstruction method unlike any other performed in Australia to date. Liberty Industrial’s proposed alternative methodology involved the erection of a circular mast climbing platform system in combination with Brokk remote controlled demolition excavators.
Working from the platform’s deck, remote controlled excavators fitted with hammer and pulveriser attachments would pulverise and hammer the concrete core of the structure and push the debris inside the tower shaft. The rubble would then be collected via an opening at the base of the tower and transported off site for recycling.
A high profile project with a significant degree of public interest, stakeholder management was an essential component of the project given the proximity and potential impact of the project on neighbouring residents local businesses and park visitors.
A comprehensive environmental monitoring program was implemented to monitor dust, noise, vibration and meteorological data, which included measuring wind speed, wind direction and rainfall to ensure compliance with strict regulatory approval conditions. Environmental factors such as noise, vibrations and dust were constantly monitored and reviewed against the authorised levels set by the project’s authorities.
The first stages of the project consisted in erecting the circular mast-climbing platform system and assembling a 20m-high ‘dust-proof wall’ separating the works from the surrounding underground cultural space at the base of the tower. Following adequate engineering assessment, the base of the tower was also cut out to create a catchment area to receive the demolition materials.
All asbestos containing materials were then removed from inside the tower. These operations were carried out in accordance with all relevant statutory requirements, standards, codes and guidelines and adequate clearance certificates were provided when required.
The first demolition works consisted in removing all equipment and machineries inside the tower, such as the elevator and associated services, and the steel stairs. The purpose was to clear the inside of the tower by removing all items with a potential to obstruct the path of the debris directed into the shaft during the demolition.
Without any mean to access the top of the tower from the inside anymore, access for personnel would be via the mast-climbing platform, which was equipped with a men and materials hoist.
The control and operations room at the top of the tower was then deconstructed by hand, working simultaneously from inside the building, and outside on the mast-climbing platform’s deck.
Following the removal of the control room’s steel structure and equipment, the remote control excavators were loaded onto the platform and started demolishing the tower’s core and slabs.
The environmental impact of these machines is incredibly low in terms of noise, dust and vibration in comparison with classic demolition tools and equipment such as hand held jack hammers and concrete saws. They also provide a major improvement in terms of personal safety as they are remote controlled, thus reducing considerably the risk of direct personnel exposure.
Safer, and quieter than other plant and equipment, they eroded the circumference of the tower with the resulting rubble pushed into the tower shaft. The debris were collected in the underground space at the base of the tower and transported off site for recycling.
Progressively, the tower diminished in height, and the platform followed, lowering itself to constantly provide an adapted work area around the tower core.
Once the tower reached street level, leaving only 20m left in the underground event space to be demolished, the mast-climbing platform was dismantled and replaced with a mobile crane fitted with a concrete pulveriser. The tower was then demolished until the foundations were exposed. The tower’s concrete foundation was then fractured and removed.
The final stages of the works consisted in excavating the sandstone at the base of the tower and constructing a brand new trafficable ground slab to extend the underground event space. Liberty Industrial also reinstated the surroundings of the tower which included the construction of new landscape areas blending into the existing Headland Park.
Project resource recovery exceeded 98% of all materials with only 2% of the waste generated going to landfill.
The project team’s extensive experience delivering high profile and complex deconstruction projects was critical to achieving minimal disruption to the local community and upholding rapport with project stakeholders.
With the removal of the tower, the vision of a naturalistic-looking headland has finally been achieved, creating an open and natural public space for the local community and visitors to enjoy.
The project was shortlisted as a finalist for the 2017 World Demolition Awards in the ‘Urban Demolition’ award category.