Construction of the first two of four new multi-level buildings linked by a see-through atrium at Deakin University’s Burwood, Melbourne campus is being fast-tracked using a design/construct methodology in which the design has been undertaken in tandem with the commencement of building.
Part of the University’s central precinct project, the new facilities will include a lecture theatre, a multi-use sports hall, teaching spaces, a restaurant and food court. Expected to be ready by the end of this year, the rapid construction timetable has been facilitated in part by the use of precast concrete on walls and floors on the two primary structures, with one entirely precast, using hollowcore plank’s long-spanning ability to eliminate conventional concrete beams and therefore the need for formwork.
Westkon Precast Concrete supplied all precast for the project, including wall panels, columns, prestressed and normally reinforced beams, balcony panels and extensive areas of hollowcore flooring comprising inverted tee-beams and planks spanning up to 8m in length and 1.2m wide, provided by Westkon’s Sunshine factory.
Hollowcore planks were also used to form several of the areas at roof level with steel used elsewhere. Generally, 200mm hollowcore planks were used, with some 300mm planks used in the West Building loading bay to accommodate the higher loading from trucks. At ground level, hollowcore was used to span between in-situ concrete ground beams. The prestressed inverted tee beams were 350mm deep by 1050mm wide, spanning about 8.4m with some cantilevering out a further 3m. These beams were unpropped during construction to enhance speed of erection and provide immediate access under the floor after casting the screed.
Precast columns off steel moulds ensured a smooth surface requiring only paint for a finish. A total of 104 columns, conventionally reinforced, were provided.
Wall panels were load bearing and fixed by a weld connection and grout tube. Some 94 wall panels were supplied off-form steel mould for a smooth painted finish; all joints being chamfered with face seals.
The structural engineering design and documentation of the full precast structure was completed by Worley as a sub-consultant to Westkon for the overall design and construct contract of the precast structure. Worley produced the shop drawings for all the flooring elements, all columns and most walls.
Environmentally Sustainable Design (ESD) features were integrated with the precast concrete structures with specialists environmental design consultants engaged by the University to provided detailed input into the design process. Together with project designers H20 Architects, they worked to ensure that the buildings achieve extremely high standards of energy efficiency, both in construction and in ongoing operation.
The project is designed to maximise the benefits of thermal storage delivered by precast concrete, together with the use of natural lighting to reduce the impact of heat loads from artificial lighting.
The efficiency and fine appearance of the “all precast” walling and flooring structural useage on the two central precinct buildings has been recognised in the early planning for follow on buildings elsewhere on the campus. Early design parameters for the proposed new buildings utilise precast, with the added possibility of using the voids in the hollowcore flooring as innovative air ducting.
The carparks
A staged program of carpark at Deakin University’s Burwood campus is similarly providing a model of economy and speed of construction. Using a combination of structural steel and Stramit Condeck HP composite formwork, the first stage was a two storey structure built above an existing ground level carpark during the 1997-98 university vacation.
Meeting this tight deadline, with only eight weeks for steel and formwork erection, required co-ordinated planning, off-site fabrication and outstanding teamwork by all involved.
The combination of a structural steel frame and 120mm composite slabs was the only way to meet Deakin’s time and cost restraints. The two suspended levels provided Deakin with an additional 9800sq m of parking.
Because of the success of this project, a duplicate carpark was built beside the first, using the same team and an identical schedule, during the 1998-99 holidays.n