Casebook

Stramit Condeck HP®

composite decking

How builders are making the most of

Condeck®

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1 >Thinner slab with less reinforcement2 >Fully enclosed ribs increase bond and act as FER3 >Improved thermal performance (�-hour fire rating on 1�0mm slab)4 >Shear studs up to 100mm centres for optimal composite beam action5 >Better end span performance with the Stramit Condeck Plus™ accessory6 >Flat soffit – no voids above intermediate walls

After the building is completed, the Condeck slab keeps working

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Stramit Condeck HP®

composite decking

Solid performance from a composite slab

Stramit Condeck HP® composite decking offers all the advantages of a solid slab, with the added savings of a composite slab. Because the ribs are fully enclosed in concrete, the Stramit Condeck HP® composite slab has the thermal and acoustic advantages of a solid slab. There are no gaps to compromise thermal performance and no voids to limit the placement of shear studs.

Stramit Condeck HP® decking also makes a significant contribution to the performance of the slab. These benefits can add up to significant savings on multi-storey buildings.

>Thinner slabs mean lower building height, with savings on columns and exterior cladding.

>Shear stud flexibility means smaller beams. Or savings in studs and longitudinal reinforcement.

>There is usually no need for positive reinforcement and often no need for fire emergency reinforcement. The fully enclosed ribs remain cool and act as FER.

Other decks may offer greater spans, and may span further during formwork construction… but bigger deck spans normally lead to bigger beams, thicker slabs, greater crane loads and potentially higher construction costs.

Stramit Condeck HP® decking can optimise the composite slab for economy and fire performance, for the life of the building.

Software takes hard work out of design

Design time can be slashed from days to minutes using the Stramit Condeck HP Slab Designer™ software on CD-ROM. Engineers can now create optimised slab designs quickly and easily in formwork, composite and fire modes.

This easy-to-use program provides metal formwork, composite slab, moment redistribution and FER calculations using data for spans, slab thickness and loads. Moments, shears and deflections can be calculated and compared with capacities in both formwork and composite slab modes.

Call Stramit Building Products now to arrange a demonstration.

Front Cover: Southern Cross Development, Melbourne

Melbourne’s landmark Southern Cross development, on the iconic Southern Cross Hotel site, is being developed and constructed by Multiplex. The recently completed first stage includes the 38-storey East Tower and the sub-structure of the future West Tower. Some 95,000 square metres of Stramit Condeck HP® composite decking was installed by SES Structural Erectors for the composite slab floors of the steel-framed East Tower.

Steel fabricator: GVP Fabricators. Steel erection, deck and shear stud installation: SES Structural Erectors.

Project Reviews

How builders are saving time, labour and materials with Stramit Condeck HP® composite decking

Commercial & Retail

Westfield Bondi Junction 4 Latitude @ World Square 10 Southern Cross Development 1� Mt Waverley Offices 13 Holden Headquarters 15 Hong Kong Skyscraper 16

Commercial Units

Surrey Hills 16 Ringwood 17

Public & Institutional

Brisbane Magistrates Court 5 Southern Cross Rail Station 14 Casey Hospital 18 Epworth Eastern Hospital 18

Residential

Freshwater Place 7 Express Apartments 8 Portico Apartments 9 The Conder Apartments 19 Watermark Apartments 19

Carparks

Brisbane Airport Carpark 6 Maroondah Hospital Carpark 11 United Carpark 17

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Contents

Project Westfield Bondi Junction Eastern Sydney

Building type Retail redevelopment

Construction method Concrete frame Post-tensioned band beam slabs In situ metal formwork

Developer/builder Westfield Group

Structural engineers MPN Group

Post-tensioning system Austress Freyssinet

Formwork contractors Wideform Constructions Dolso Constructions

Westfield triumphs over biggest Sydney challenge

The Westfield Group’s most ambitious retail redevelopment in Sydney was a $700 million shopping and entertainment complex at Bondi Junction, in the heart of Sydney’s affluent eastern suburbs.

The new complex consolidates three existing retail sites on two blocks to create a mega-centre with more than 100,000 square metres of retail space. In terms of size, site restrictions and limitations on working hours and access, this was probably Westfield’s greatest challenge in Sydney.

The concrete floors incorporate 135,000 square metres of Stramit Condeck HP® composite decking, which was used as in situ formwork on the post-tensioned band beam slabs to speed construction.

The need to minimise the number of trucks entering the site was a major influence on the decision to use in situ steel formwork for the floor slabs. Ease of handling and the fast installation time of Stramit Condeck HP® decking, combined with the lack of stripping out, helped complete the project within the timeframe.

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Westfield Bondi Junction

Using Condeck significantly reduced material handling on the project. It went down really fast – it’s ideal for that sort of job. There were fewer trucks, less handling and less wastage – delivering plywood formwork and stripping it out afterwards would have been very difficult and time-consuming on that site.

Teddy Ferreira Wideform Constructions

Switch to steel formwork saves time and money

A late conversion from conventional formwork to metal decking saved time and money on the new Brisbane Magistrates Court building.

The 10-storey concrete-framed building was originally designed with post-tensioned flat plate floors and drop panels using conventional formwork. However, a sharp rise in formwork rates caused the builder to value-engineer the design.

A new floor system was developed by builder Walter, structural engineers Robert Bird & Partners and post-tensioning specialist Austress Freyssinet. The solution featured wide band beams and one-way post-tensioned slabs incorporating

Brisbane Magistrates Court

Stramit Condeck HP® composite decking.

Walter’s project manager, Alan Robertson, said the switch to metal formwork saved on time, labour and materials handling without adding to construction costs.

“There are obvious savings in materials handling because the Condeck bundles are delivered cut to length and you just have to walk it on.” Alan said.

“There are also collateral benefits, such as the clean finish, the ease of fixing the services and the fact that you are working in a more dust-free and generally safer environment.”

Project Magistrates Court

Brisbane City

Building type Institutional

Construction method Concrete frame

Post-tensioned band beam slabs

In situ metal formwork

Owner Qld Department of Justice

and Attorney General

Managing contractor Walter Construction Group

Project manager Qld Department of

Public Works

Architects Ainsley Bell & Murchison

Cox Rayner

Structural engineers Robert Bird & Partners

Post-tensioning system Austress Freyssinet

Formwork contractors Wideform Queensland

We were able to take back five weeks of lost time because of the speed of installation and reduced back propping

Alan Robertson Project Manager

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Steel frame solution increases parking capacity

An upper extension of a carpark at Brisbane Airport took advantage of the light weight of steel to squeeze in an extra level of parking.

The existing long-term carpark at the domestic terminal was constructed in �000 with future expansion in mind. The foundations and columns of the concrete-framed, three-level building were designed to support two more levels when required.

Barclay Mowlem was awarded the design and construct contract for a concrete-framed upper extension. However, demand for parking space meant only the top level could be accessed during construction. Building the extension in concrete would have required back propping on both the existing suspended floors.

Steel was the obvious alternative. Barclay Mowlem and structural engineers Robert Bird & Partners redesigned the extension in structural steel and calculated that an extra level could be included.

The speed of erection of the structural steel frame and metal deck kept the project on track, despite the redesign, providing the increased carparking capacity earlier than expected.

The extension includes �000 tonnes of structural steel, supplied by Beenleigh Steel Fabrications, and 50,000 square metres of Stramit Condeck HP®

composite decking for the suspended slab floors. An added benefit of the Condeck HP® deck is the absence of voids in the soffit, which simplifies maintenance by providing a flat surface for painting.

Brisbane Airport Carpark Extension

Project Carpark Expansion Brisbane Airport

Building type Multi-level carpark

Construction method Steel frame Concrete slab floors In situ metal formwork

Owner/developer Brisbane Airport Corporation

Design & construct Barclay Mowlem

Structural engineers Robert Bird & Partners

Steel fabricators Beenleigh Steel Fabrications

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Panellised formwork solution for major high-rise

Melbourne’s $750 million Freshwater Place development is a mixed residential, commercial, retail and civic project featuring three towers above a podium. One tower is for commercial use and two will be residential.On the 7-level podium and the 36-level commercial tower, builders Baulderstone Hornibrook sped construction

Freshwater Place

with prefabricated components, including precast columns and custom-made steel formwork panels.

The formwork panels provide a complete bay of decking between band beams and incorporate Stramit Condeck HP® composite decking supported on modified Stramit® C300 Purlins. When the panels are placed on site, the 300mm purlins provide the edge form for the band beams.

The 4.5 by 1�.5 metre panels were fabricated off-site by Omniform and transported in a special stillage that could be craned on to site if required. The formwork panels utilised Stramit Condeck® Shades anti-glare composite decking with a special coating to reduce glare and improve worker comfort and safety.

Project Freshwater Place Melbourne CBD

Building type Commercial high-rise

Construction method Precast concrete columns

Composite band beam slabs

Prefabricated formwork panels

Developer Australand

Builder Baulderstone Hornibrook

Architects Bates Smart

Structural engineers Winward Structures

Formworkers Caelli Constructions

Formwork fabricators Omniform Group

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We used the composite properties of Condeck to optimise the slab design.

Fire emergency reinforcement was also reduced, using the solid-slab fire

properties of the Stramit decking. The bottom reinforcement, which is

attached to the panels during fabrication, is only a light mesh for shrinkage.

Peter Hindmarch Winward Structures

Project Express Apartments Richmond, Victoria

Building type Residential redevelopment

Construction method Steel-framed upper extension on concrete and masonry building

Developer/builder Baracon Group

Structural engineers Adams Consulting Engineers

Formwork contractor Concorp

Steel solution adds four levels to heritage building

Baracon Construction successfully transformed a unique industrial site in the Melbourne suburb of Richmond into 91 new apartments by redeveloping the existing factory building and adding a steel-framed upper extension.

A heritage order required the outer shell of the old building to remain, which created additional design challenges for Interlandi Mantesso Architects.

The existing two-storey building was constructed from concrete-clad steel beams and columns with concrete floors. The structure was analysed to ensure the columns and footings could support the new building.

Two new intermediate levels were added between the existing floors for car parking, then a four-level extension was constructed above from a steel frame and composite slabs.

Structural engineers Adams Consulting Engineers used the composite and fire properties of the Stramit Condeck HP® slab to create a 150mm slab with reduced fire emergency reinforcement. They also took advantage of the flexibility in placement of shear studs to create composite beams that saved on beam weight and depth.

The steel frame and deck solution provided for quick construction, much faster than anticipated according to formwork contractors, Concorp.

Express Apartments

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Landmark church resurrected as luxury units

The magnificent Scot’s Church building in the Sydney CBD has gained a new lease of life as the Portico luxury apartment complex. The $110 million redevelopment preserves the original structure and façade while accommodating a new steel-framed extension above the heritage building.

Because the upper extension is founded on the old structure, a lightweight construction solution was devised by developer-builder Westpoint, architects Tonkin Zulaikha Greer and structural engineers Van Der Meer Bonser.

Portico Apartments

The extension is a steel-framed structure with composite floors 100mm to 150mm deep incorporating Stramit Condeck HP® composite decking, as well as timber-framed mezzanine floors, curtain walls and a metal deck roof.

A major complication for the builders was the proximity of the Sydney underground rail network. Any load imposed on the building was also imposed on a rail tunnel 4 or 5 metres under the building. An additional design constraint was that extra loadings could crack the heritage sandstone façade.

Even the slab depths were varied across the same level. By following the Stramit® fire design procedure, the floors also saved on fire emergency reinforcement.

Project Portico Apartments

(Refurbishment of Scot’s Church) Sydney CBD

Building type Multi-level residential

Construction method Steel frame

Composite floor slabs

Builder/developer Westpoint Corporation

Architects Tonkin Zulaikha Greer

Structural engineers Van Der Meer Bonser

Fabricators Universal Steel Constructions

(Aust)

Deck & studs Santana & Co.

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I prefer a solid concrete deck section because of the design flexibility. There

are no acoustical issues as with re-entrant decks, where the voids may have to be

filled in above partition walls.

Milton Webster Van Der Meer Bonser

Composite technology revives stalled tower

An abandoned concrete tower at Sydney’s World Square site was rescued by an advanced composite steel-and-concrete solution that overcame a host of site limitations to complete the building.

Construction of the concrete-framed building began in 1988, in an overheated economic climate, but was soon abandoned by the developers. The partly built structure remained a prominent blight on the cityscape for the next 15 years.

Under a new development plan by Multiplex, the building was completed in �004 based on a new building design by Crone Nation. The gleaming façade of the 55-level tower conceals the transfer solution by engineers,

Hyder Consulting, which allowed Multiplex to complete the building using composite steel columns and decks above the existing concrete structure.

The new tower comprises composite floors on steel beams clear-spanning up to 14 metres from the services core to the perimeter columns. The composite columns are pairs of concrete-filled steel tubes. The double-storey transfer trusses were also made from concrete-filled steel tubes and box girders.

Engineers from Stramit Building Products worked with Hyder Consulting to take advantage of the excellent composite and fire properties of the Stramit Condeck HP® decking system. Only a light F7� reinforcing mesh was required throughout.

Latitude @ World Square

Project Latitude @ World Square (Ernst & Young Centre) Central Sydney

Building type Commercial high-rise

Construction method Composite columns Composite floor slabs Steel beams

Owner/developer/builder Multiplex Constructions

Architects Crone Nation

Structural engineers Hyder Consulting

Steel fabricator & erector Alfasi Steel Constructions

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Maroondah Hospital Carpark

Latitude @ World Square

Long-life steel formwork cuts maintenance

A long-life version of Stramit Condeck HP® composite formwork contributed to a maintenance-free finish on a multi-level carpark at Maroondah Hospital in Melbourne.

The decking was rolled from ZAM material, which has an advanced hot-dip coating that provides outstanding corrosion resistance, with an expected lifetime at least three times that of conventional galvanised steel in severe environments.

The Mackie Group won the design and construct tender against some larger builders with a smart solution featuring a post-galvanised steel portal frame and composite slabs with the ZAM-coated Stramit® decking.

A long, maintenance-free life

was assured for the building by the combination of pre-finished steel and precast concrete, with the added benefit of speed of construction. A team effort by the family-owned Mackie Group and its contractors allowed the project to be handed over a month ahead of schedule.

The four-level structure features structural composite beams at �.6m centres, which allowed the slabs to be poured without centre supports. The 1�0mm slabs take advantage of the reinforcing property of the Stramit Condeck HP® ribs to eliminate bottom reinforcement.

A further benefit of the ZAM coating is its uniform metallic lustre, which provided a quality metallic finish to the underside of the slab that reduced the need for artificial lighting.

ProjectMaroondah Hospital

Carpark Victoria

Building type Multi-level car park

Construction method Steel portal frame

Composite beams and slabs In situ metal formwork

Builder/developer Mackie Group

Structural steel F&B Skrobar Engineering

Formwork contractors I&D Formwork

Deck & studs Rican Contractors

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We found the Condeck very easy to work with - the speed of prop-free

construction allowed us to finish well ahead of schedule. The ZAM material

also provided an aesthetically pleasing finish as well as contributing

to a maintenance-free structure.

Joe HastieMackie Group

The landmark Southern Cross development is situated on the iconic Southern Cross Hotel site at the eastern edge of the Melbourne CBD. The site, which will eventually feature two towers, is being developed and constructed by Multiplex.

The recently completed first stage includes a five-level basement carpark, the 40-level (165-metre) East Tower and the sub-structure for the West Tower.

The East Tower (SX1) has a regular floor plate and central services core. Some 95,000 square metres of Stramit Condeck HP® composite decking was installed by SES Structural Erectors for the composite slab floors of the steel-framed tower.

The building was designed using environmentally sustainable principles of construction and operation, with a double-glazed façade that will reduce the long term operating costs and substantially benefit the local environment.

A driving force in the commercial brief was the trend towards larger floor plates rather than higher buildings. SX1 has a centrally located concrete core and only one row of columns at the perimeter, delivering typical 14-metre spans and column-free spaces of �650 square metres.

Continuous metal deck formwork spanning 3 metres between secondary beams was used to support the 1�0mm thick floor slab, with continuous top reinforcing fabric. On the eastern façade, the slim profile of the Stramit Condeck HP® slab was used to extend glazing from the floor to the underside of the slab above, maximising views and natural light.

The unpropped steel acting compositely with metal deck formwork was the most cost-effective solution for the tower. Other advantages of the steel solution were simplicity, ease of construction, minimisation of on-site trades, fast floor turnaround time and reduced traffic and site congestion.

ProjectSouthern Cross Development Melbourne CBD

Building type Commercial high-rise

Construction methodSteel frame Composite floor slabs Steel beams

Developer SX Developments

Design & construct Multiplex Constructions

Architects Woods Bagot

Structural engineers Bonacci Group

Steel fabrication & erection GVP Fabricators

Steel erection, deck & studs SES Structural Erectors

Southern Cross Development

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Project Twin Office Buildings Mt Waverley, Victoria

Building type Commercial

Construction method Precast concrete columns

Composite band beam slabs

Builder/developer CGA Bryson

Architects Miller Watson Architects

Formwork & concrete Oceania Universal Paving

Metal deck and precast columns speed construction

An unconventional site provided the opportunity to move away from traditional office park design for a commercial development in the Melbourne suburb of Mt Waverley. The site boundaries form a complex shape and the constraints of easements and setbacks significantly reduced the usable land for development.

Builder/developer CGA Bryson and designers Miller Watson Architects avoided a typical response such as a two-storey office with a single large floor

Mt Waverley Offices

plate and undercover parking. Instead they created two four-storey buildings with a common basement carpark, linked by a central plaza for pedestrian circulation and recreation.

To speed construction, concreter Oceania Universal Paving opted for steel formwork and precast concrete columns. Rocla Building Products supplied 84 columns up to 11 metres high, with built-in fittings for connection to other building elements.

A bolted base connection allowed immediate erection of free-standing columns, while block-outs in the columns at the required levels allowed for easy construction of band beam floors using Stramit Condeck HP® composite decking.

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We combined precast columns with composite Condeck slabs and conventional

band beams. We chose Condeck for its speed of erection compared with plyform.

The precast columns, band beams and Condeck slabs integrated very well and

worked as a system. We were very happy with the progress.

Damien Milano Oceania Universal Paving

supports a vast wave-like roof structure - 37,000 square metres in area and �3 metres at its highest point - plus an arrivals hall with glass street frontages.

The station remained fully operational during construction, moving more than 50,000 people a day. To maintain rail services, a major proportion of the work was undertaken at times that minimised disruption to both services and passengers.

Permanent metal formwork was used on the suspended concrete

Spencer Street Station Redevelopment

Project Southern Cross Station (Spencer St Station Redevelopment)

Building type Rail terminal

Construction method Steel frame Composite slabs In situ metal formwork

Developers Civic Nexus Consortium

Architects Grimshaw Jackson Joint Venture

Construction Leighton Contractors

Structural engineers Winward Structures

Formwork & concrete DECCO

Prop-free composite slabs keep trains running

A massive overhaul of Spencer Street train station in Melbourne has transformed it into a modern, airport-style transport facility.

As part of the redevelopment, the old 1960s terminal was replaced with a new transport interchange facility, designed and constructed by Leighton Contractors, with a total project value of approximately $700 million.

A steel-framed structure built above the existing platforms

slabs to allow prop-free slab-laying above rail lines and busy areas, as well as to speed the construction process. Stramit Condeck HP® composite decking was used to construct suspended slabs in the Collins Street and Spencer Street concourses, as well as the Bourke Street pedestrian bridge.

The new station, renamed Southern Cross Station, provides a world-class transport and interchange facility as well as a gateway to Melbourne’s Docklands redevelopment.

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Metal formwork revs up construction for Holden

Stramit Condeck HP® composite formwork helped Baulderstone Hornibrook deliver Holden’s new headquarters on time by speeding up floor construction on the three-level office building and adjoining six-level car park.

The office structure involved the erection of seven concrete lift shafts using precast panels, as well as post-tensioned suspended concrete slabs on band beams and metal formwork, which allowed greater floor-to-ceiling heights and easier installation of services.

Project Holden Headquarters

Port Melbourne

Design & construct Baulderstone Hornibrook

Office building Concrete frame

Post-tensioned band beam slabs

In situ metal formwork

Formwork Eurocrete Construction

Carpark Steel frame

Composite beams and slabs In situ metal formwork

Steel fabricators GVP Fabricators

Deck & studs SES Structural Erectors

Holden Headquarters

For the car park, three precast concrete cores were erected, followed by a combination of approximately 1000 tonnes of structural steel and suspended concrete slabs on composite beams.

A proactive relationship between Baulderstone Hornibrook, unions and the client produced a high-quality building within a tight construction program.

The new headquarters will house staff from six existing sites within the Port Melbourne precinct, consolidating the majority of Holden’s workforce of engineers, designers, administration and executives under one roof.

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333 Canterbury Road Surrey Hills, Victoria

4�0 metre Hong Kong Skyscraper

This 88-storey tower in Hong Kong employs an “outrigger” design for lateral stability, with a rigid central core wall and eight mega-columns (two on each face) plus secondary columns in the four corners forming the external steel frame.

To provide unobstructed views, large edge girders were used to support the floors between the main columns, spanning up to �4 metres.

The floor system is a 1�5mm thick composite slab supported on steel beams. Some 150,000 square metres of Stramit Condeck HP® composite decking (1.0mm base metal thickness) were used in the tower floors.

Stramit Condeck HP® decking is manufactured in Singapore under licence by LCP Building Products Pte Ltd.

Project Retail Development Surrey Hills, Melbourne

Building type Low-rise commercial

Construction method Steel frame Composite floors In situ metal formwork

Design & construct CGA Bryson

Formwork Brishoney Nominees

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333 Canterbury Road Surrey Hills, Victoria United Carpark

45 Ringwood Road Ringwood Victoria

Project Carpark

Tullamarine, Melbourne

Building type Multi-level carpark

Construction method Steel frame

Composite floors In situ metal formwork

Builder Pritchard

Steel fabricators Trojan Engineering

Formwork Composite

Support Systems

Project Retail Development

Ringwood, Melbourne

Building type Low-rise commercial

Construction method Steel frame

Composite floors In situ metal formwork

Builder/developer CGA Bryson

Formwork Composite

Support Systems

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Epworth Eastern Hospital

Casey Hospital

Project Public Hospital Berwick, Melbourne

Building type Multi-level medical

Construction method Steel frame Composite floors In situ metal formwork

Owner/developer Dept Human Services, Victoria

Architects Silver Thomas Hanley Daryl Jackson

Builder Multiplex

Formwork & concrete DECCO

Deck & studs SES Structural Erectors

Project Private Hospital Box Hill, Melbourne

Building type Multi-level medical

Construction method Concrete frame Post-tensioned slab floors In situ metal formwork

Owner/developer Epworth Hospital

Builder Abigroup

Formwork & concrete Eurocrete

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Casey Hospital

Watermark Apartments

The Conder Apartments

Project Residential Development

New Quay, Docklands

Building type High-rise residential

Construction method Concrete frame

Composite floors In situ metal formwork

Developer MAB Corporation

Architects Synman Justin Bialek &

Fender Katsalidis

Builder Bovis Lend Lease

Formwork DISO

Project Residential Development

Brighton, Melbourne

Building type Multi-level residential

Construction method Steel frame

Composite floors In situ metal formwork

Formwork Eurobuild

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Contact Stramit Building Products and discover how you can make slabs of savings with Stramit Condeck HP® composite decking

NSW/ACT (02) 9834 0900

QLD/NT (07) 3803 9999

VIC/SA/TAS (03) 9237 6200

WA (08) 9493 8800

5947

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