|Tasman Highway – Hobart Airport Interchange
|Department of State Growth
The Hobart Airport Interchange project was required to replace the existing Hobart Airport roundabout with a solution that improved the existing traffic congestion and allowed for high projected growth for the Hobart Airport and the Sorell/Cambridge area.
After an initial design phase, the Department of State Growth elected to undertake the project as design and construct contract model to allow for innovative solutions from the industry. During the tender phase, Hazell Bros partnered with designer Cardno and proposed raising the Tasman Highway over the intersection, a design solution focused on the following key items:
The final design of the interchange was comprised of the following key items:
Upgrades to local roads to improve access safety to local businesses and the Hobart Airport
|Rosebery Tailings Dam Upgrade
|Minerals and Metals Group (MMG)
In 2016/17 Hazell Bros was engaged by MMG to upgrade the Rosebery Tailings Dam. Some of the works included:
Awarded the Tasmanian Civil Contractors Federation Earth Award in 2018 - Category 5 Project value between $30M and $75M.
|Conglomerate Dam Upgrade
Built in 1971 of earth and rockfill construction, Conglomerate Dam has a storage capacity of 53.1ML. In 2017 Hazell Bros was engaged by TasWater to undertake an upgrade of the dam. Some of the works included:
This is the largest contract ever awarded to the business in its own right.
Works included 48 turbine footings, each averaging 450m3 of concrete; 26km of access roads; crushing and screening of road building material on site; steel fixing; management of 40km of electrical reticulation cabling; construction of substation, including control building; and operations and maintenance building.
Works included construction of 24km access roads; establish and operate two mobile concrete batch plants to produce 15,000m3 of concrete; construction of 25 16.6x16.6m reinforced concrete footings for the towers, each containing 40T reinforcing steel and 450m3 concrete; construction of 25 45x45m hardstands; design and construction of control building; construction of switchyard footings; installation of 25km of underground cables; and civil works for 5km of transmission line, including temporary access roads and pole footings.
Works included construction of control building and associate switchyard footings; construction of 45km of internal road network and associated local road upgrades; construction of 56 octagonal reinforced concrete footings for the towers; onsite quarrying of road building materials; establishment and operation of two mobile concrete batch plants; and establishment of a fully-equipped 80-person construction camp in Gladstone.
|East Devonport, TAS
|Ports & harbours
The joint venture project will deliver an upgrade of the existing Berth 3E to make it suitable for operation, including berthing, mooring and stern-loading of a roll-on roll-off (ro-ro) ship up to a length of 212m, for both passengers and freight between Geelong, VIC and Devonport (new Spirit of Tasmania vessels).
The scope of the works under the contract includes:
The project has adopted the use of 8T rock bags as scour protection in the berth in lieu of large rock and associated additional dredging. This is the first time in Australia that these rock bags have been used in this application. The bags are also made from recycled materials and are filled with rock from a local Hazell Bros quarry.
The wharf piles are coated with a 3-layer polyethylene (3LPE) coating system to increase the durability of the piled structure and lower life cycle costs for the asset owner.
Works have been carried out with strict environmental monitoring to ensure compliance to relevant water quality, turbidity, noise and dust standards. Site reuse of material has been maximised where possible with dredge rock and concrete demolition waste being crushed on site and reused in the reclamation areas.
The project is due for completion in May 2024.
|Lake King William, TAS
The project involves construction of the intake excavation and downstream portal for the first stage of a new water conveyance directing water from Lake King William down to the Tarraleah Power Station. The 2 excavation sites will eventually be connected by a tunnel to allow the water to be piped through the surrounding mountains.
A plastic concrete cut-off and wave bund coffer dam were first constructed to protect the intake excavation from the rising lake levels and allow excavation to continue unimpeded. Excavation of ~130,000m3 of glacial soil and ~120,000m3 of dolerite rock is required at the intake site to reach the invert of the future tunnel.
Ground support is required to protect the steep excavation batters at both excavation sites, with a significant amount of rock bolts and shotcrete to be installed.
The project is due to be completed mid-2024.
|Don and Lower Barrington, TAS
The project involved laying of approximately 50km of distribution pipeline for two irrigation schemes; the Don Irrigation Scheme which draws water from the Forth River, and the Barrington Irrigation Scheme from Lake Barrington.
The pipeline was constructed with buttwelded 20m lengths of DN560 and smaller HDPE pipe.
The pipeline accessed 123 privately owned properties with 69 property outlets installed.
Installation of the pipeline encountered high production cropping farms, extreme wet weather, hard rock, and water, service and road crossings.
The project was completed in 14 months.
This project involved the demolition of 8 existing buildings on the former Gunns sawmill site in Smithton.
Key considerations relating to the risks associated with the demolition of the buildings:
Innovative thinking and planning for the project include the re-use of clean fill/rubble from the site to construct hard-stands for felled timber storage on a neighbouring property, along with fill for existing pits on-site. Scope of works included demolition of all buildings, services, structures and equipment that exist on the site to the top of the ground floor slab surface level or exterior surface.
The demolition works at the Royal Hobart Hospital in Hobart’s CBD was part of the larger construction works undertaken by the John Holland / Fairbrother joint venture to replace the hospital’s B Block with a new K Block, while the hospital remained fully operational. Hazell Bros was awarded the subcontract tender for the demolition of B Block located in the northwest corner of the hospital complex. The project was successfully completed through in-depth staging that allowed machinery to reach the higher levels of the building’s “tower” by constructing a ramp comprised of debris from the lower levels.
Scope of works included:
Demolition of the existing Block B involved substantial technical, physical and logistical challenges that had to be overcome for successful project delivery.
The demolition work was completed within a live hospital environment which required:
Hazell Bros was a Category 2 Winner at the Tasmanian 2017 CCF Earth Awards for the Royal Hobart Hospital Redevelopment – Block B Demolition.
|John Holland Fairbrother Joint Venture
10 Murray St forms part of the Parliament Square precinct, with the project site bordered by Parliament House, Salamanca Building and 34 Davey St. Stage 2 of the Parliament Square Redevelopment involved demolition of the 13-storey 10 Murray St building, retentions of the 12 Murray St heritage facade, and demolition of the 12 Murray St building.
Due to the proximity of the works to neighbouring occupied office buildings and businesses, additional environmental considerations were adopted for the duration of the works including dust, noise and vibration monitoring. Specialised contractors were engaged to install monitors and track levels with additional noise monitoring conducted in sensitive areas.
Additionally, regular meetings were held with stakeholders to communicate where the work program and construction methods were presented to inform people of what they could expect in the progression of the works, how the dust, noise and vibration are being managed. This also provided a platform for Hazell Bros to understand what the stakeholders’ concerns were through project delivery.
The design maximised the footprint of the demolished 10 and 12 Murray St buildings presenting challenges in maintaining the structural stability of the surrounding buildings during project delivery. The construction required 800m3 of material to be excavated. Survey monitoring points were established on buildings adjacent to the site, including the maintained heritage façade, to measure any movement during excavation and construction of the retaining wall.
The 10 Murray St groundworks involved excavation of the site approximately 12m below existing ground level and 0.5m below sea level. This presented significant challenges with the ingress of groundwater during piling and excavation.
Construction of the retaining wall consisted of 172 contiguous bored piles and 140 ground anchors. The design and installation of the ground anchors had to consider the surrounding building structures and underground services, particularly where they were installed under the existing Murray St road.
|Citta Property Group
This project involved the demolition of the Jacksons building at 231-235 Wellington Street in Launceston.
Key considerations were given to mitigate the risks associated with the demolition of the buildings:
The scope of works included the complete demolition of the concrete building, removal of steel roof trusses, excavation of footings and transportation/disposal of demolition waste.