Ambulances and SuperTs cross paths on hospital busway site

June Cummings reports

Called the Northern Busway (RCH to Windsor section), the $198m project was an alliance between Queensland Government, Abigroup (construction and engineering) and SMEC (design) to build a busway and station servicing a hospital, while ambulances screamed into emergency bays and hospital traffic flows remained unhindered at all times. Brisbane’s designated busways are a key part of its future traffic management plan.
The Northern Busway infrastructure links with the Inner Northern Busway. It includes a three-level busway station with inbound and outbound platforms servicing the Royal Brisbane and Women’s Hospitals, a covered walkway into the hospital, and a bus-only connection to Bowen Bridge Road over the Inner City Bypass and QR freight line.
Part of the brief was the inclusion of sustainable design features such as solar power, rainwater harvesting and natural ventilation and lighting.
What a joy to ‘fly’ through the city on the Inner Northern Busway and the Northern Busway, disembark at the light and airy hospital bus station and be greeted with a huge electronic billboard – not advertising a sleek car, but how many litres of water had been harvested over the last week and how many kilowatts of solar energy generated.
Building constraints
According to Abigroup, because of proximity to the hospital and major traffic arteries, project constructibility was built into the design. Early investigations located services and other constraints. Services were relocated, lane closures were negotiated between Bowen Bridge Road for a construction area and access in and out of the work site. Much work was done at night and weekends.
The three-level busway station is in the hospital grounds, alongside the emergency department ambulance area and cantilevers over the top of a pathology unit which houses a vibration sensitive high powered microscope. Emergency access to Queensland’s premier hospital had to be maintained 24/7 and bored piling for foundations was monitored and curtailed when the microscope was in use.
With 18,000 people a day coming and going to the hospital, walking, catching buses and driving, traffic management – maintaining hospital access, finding alternative routes and keeping Bowen Bridge Road open was huge, according to Abigroup. Communication with the hospital notifying them of work planned, along with other stakeholders, as well as keeping the home work team informed of constraints and obligations, was vital at all times.
The logistics of immediacy - co-ordinating approvals such as road closures with the delivery of precast units on trucks coming in from NSW, to be lifted straight into place, was challenging. The largest mobile crane in Queensland, a 350t mobile from Lindores was on site for major lifts including the erection of the SuperTs.
A project specific precast yard was set up in nearby Victoria Park to manufacture parapets. With little or no storage on site, materials had to be brought in as required and pre-mixed concrete deliveries co-ordinated.
Construction
The 1.2km elevated structure is founded on 138 bored piles throughout its length with different types of pier construction, such as blade piers along the narrow Bowen Bridge Road corridor.
Piling in the mid section is socketed into hard rock. But the northern end had poor and contaminated ground conditions with some made up ground in places, so piling was down 25m to hard rock for sockets. Poor materials had to be removed and treated.
Headstocks cast in-situ, pre-stressed or post tensioned, varied in size depending on the 48 bridge spans. More than 180 precast concrete bridge beams up to 34m long and weighing 70t were used. Deck construction was precast planks, Super Ts or cast insitu voided slabs.  Some were cantilevered, Super Ts were used for longer spans and elsewhere two voided slab sections were cast in situ to lessen the weight.
Because of saturated market demand in Queensland, several different casting yards were used. Start-up came from Newcastle, but the majority was from Australian Precast Solutions, Macksville, northern NSW, deck units from Richmond Valley and then Contec at Darra outside Brisbane.
Innovation was ongoing. A heritage rock wall along Bowen Bridge Road was earmarked for demolition, but a solution was worked out with the Heritage Department for its preservation. The structure was redesigned and columns relocated on the footpath at this point, bypassing the wall, with the headstocks cantilevering out over Bowen Bridge Road.
The whole of the alignment has been designed to take light rail in the future, so deck finishes are asphalt, with concrete surfaces in steeper inclines.
Architectural features
The busway has been designed as an architectural feature with its non-imposing, lightweight structure sweeping in a curve on blade columns around and tying in with the hospital. At street level it has historic references with old buses and bus tickets from times past etched into the footpath.
Glass acoustic panels enclose the busway through the hospital area and decorative panels have been used on the parapets at ground level. The busway station is a steel frame and glass open structure with a covered section for stairs and vertical lift transport.
A Cycle Centre, an addition to the project, underneath the busway, will house 750 bikes, showers, lockers and bike repair facility.
If you thought the building industry epitomised a tough, macho work ethic – it has a soft heart. During construction $95,000 was raised for Royal Brisbane Hospital charities from, subcontractors, suppliers and the workforce. The money will go to the neo-natal unit, stroke research and skin bank.