Celebrating the excellent and innovative use of structural steel in buildings, the 36th Annual Steel Awards, hosted by the Southern African Institute of Steel Construction (SAISC) in partnership with Aveng Trident Steel, awarded the top steel projects completed last year on 13 September 2017.
With a Survivor theme for this year’s awards, SAISC chief executive officer, Paolo Trinchero, pointed out that despite the enormous difficulties the industry faces, companies continue to produce outstanding work, demonstrate their capability and survive.

This year’s awards saw 56 entries reflecting steel as the material of choice, involving over 300 team members. A new category, innovation, was also introduced for the first time.


Overall and Safal Steel innovation category winner: BMW H-EMS Roof Lift

The 60-year-old assembly building at BMW Rosslyn had a low saw-toothed profile roof supported by numerous columns, but the latest assembly line technology necessitated that a 4 100m² portion of the structure should be modified. Conventional roof construction methods were not possible due to limited construction time, site restrictions and ongoing operations.

Nyeleti’s extensive experience with incremental bridge launching led to the concept of launching the roof horizontally into its position.

First reinforced concrete foundations were excavated and casted within the plant. An overhead working platform had to be constructed adjacent to the tower crane, where the roof structure was constructed one roof bay at a time. As a parallel process, columns were installed on the foundations, penetrating through the existing roof. This was done over weekends, using a self-lifting hydraulic frame to lift and place sections of each column in “Lego-block” fashion. With a roof bay completed and the columns in place, the roof section was then launched hydraulically and the process repeated.

Once the entire roof was in its final position, the roof sheeting and vertical cladding commenced and once completed, the old roof was demolished. Finally, the Heavy Electric Monorail System (H-EMS) contractor suspended the new assembly line equipment from the new roof.

Teichmann Structures proposed two value engineering options: Instead of assembling the columns in sections from the ground up, the columns – 600 x 600 x 16mm steel Square Hollow sections, each 12,8m long – were fabricated as a complete unit and lifted onto the roof structure. Each column was rolled horizontally into position, using a trolley on temporary rails on top of the roof structure. Once in position above the foundations, the column would be tilted 90˚ to a vertical position, and then lowered through an opening in the roof onto its foundation.

Judge’s comment:
“I think it’s rare that you get a challenge of this type, both in engineering terms as well as fabrication and erection terms – where there is a lot of risk involved and you’re dealing with a very sophisticated owner. That’s really what is special about this – it is a very risky project, which they have pulled off spectacularly.” – Amanuel Gebremeskel, technical director of SAISC

Project team
Client/developer: BMW South Africa.
Structural engineer: Nyeleti Consulting.
Main contractor: Teichmann Structures.
Steelwork supplier and detailer: Boksan Projects.
Steel erector: Teichmann Structures, Valoworx 42cc.
Surveyor: Pristine Surveys.
Cladding manufacturer and supplier: Global Roofing Solutions.
Cladding contractor: Roofing Guarantee Company.
Temporary works engineer: ARQ Consulting Engineers.
Hydraulic equipment: Vanguard Rigging.
Corrosion protection: Dram Industrial Painting Contractors.
Nominator: Teichmann Structures.
Photographer (photo competition): Teichmann Structures.
Photographer (other images): Nyeleti Consulting.

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MiTek light steel frame building (LSFB)  category
Joint winner: Summit Place

Summit Place is the first South African high-rise office building where the facade was constructed using light steel frame (LSF) with Saint-Gobain’s ETICS external cladding. The eleven-storey building incorporates 0,8mm LSF steel frames manufactured with varying window apertures. In addition, 60mm and 90mm thick EPS panels were used to form horizontal lines between windows and on the high upstand walls on the roof patio.

Special considerations include fire breaks between floors, expansion joints at levels 5 and 7 in horizontal application and more than 700 windows in design.

This project uniquely captures many of the benefits of LSFB – the possibility to create an elegantly curved facade that was fast to install and its precision demonstrated by the fact that every single one of the 700 premade aluminium windows fitted into the allowed openings on the wall panels.

The low mass of the LSF ETICS cladding eased logistics, and made handling on site a lot easier, requiring only a small team of artisans to do the installation. Due to the low waste factor, it has a small footprint in the building, allowing other trades to work in tandem. It further provides a durable external finish as well as insulating the office building to reduce the energy required for heating and cooling over the lifetime of the building.

Project team
Client/developer: Neotrend.
Architect: Boogertman + Partners.
Structural engineer: HAGE Engineers.
Main contractor: GD Irons.
Structural steel: HAGE Engineers.
Steelwork contractor and steel erector: Ohlhorst Lightweight Building Solutions.
Cladding manufacturer and supplier: Saint-Gobain.
Cladding contractor: Ohlhorst Lightweight Building Solutions.
LSF supplier: Clotan Steel.
Nominator: Clotan Steel, Saint-Gobain.


Joint winner: GLA School Hall

With the design and construction of the new school buildings for Global Leadership Academy (GLA) in Jeffreys Bay, the challenge was creating a multi-use gathering area on a shoe-string budget. Thanks to some clever design using MiTek’s Ultra-Span high-strength, low-mass steel trusses, the architect’s vision was realised.

All trusses for the GLA school hall roof were spanned parallel to the traditional supports, essentially producing enlarged rafter/purlin type trusses. The 19m trusses were preassembled in braced pairs and then lifted into their final position on the roof to ensure fast erection of the roof structure skeleton and enabling other installation works to continue on a stable platform.

Ultra-Span girders were created at the ends to support short span trusses to comply with the required minimum ceiling height. This idea was also adopted in the middle section of the roof to act as stability braces for the window panels. Window panels were made with MiTek’s wall framing product to allow for very specific window sizes, and to provide flat surfaces for the fixing of such windows. These window panels were manufactured in several parts to ease installation.

Project team
Client/developer: Global Leadership Academy.
Architect: Pure Design Architects.
Structural engineer (site): Andre le Roux Engineering.
Engineer: MiTek Industries South Africa.
Project manager: Pure Design Architects.
Steelwork contractor and steel erector: Build IT.
LSF designer and detailer: MiTek Industries South Africa.
Nominator: MiTek Industries South Africa.

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GRS metal cladding category winner: Kasane Airport

The serpentine floor plan of the new terminal building at Kasane Airport in Botswana called for a roofing profile that could be tapered from ridge to eaves, thereby eliminating the need for unsightly kite flashings which are notoriously difficult to waterproof on flat roofs and which would have distracted from the linear image. The Zip-Tek 420 profile was chosen since it is a single pan that can be made into wedge-shaped segments in order to get a smooth flow on a curved roof.

The roof design was especially challenging as every roof sheet used on the curved sections had to be calculated and measured individually to ensure a correct radius for the curved section. The complex geometry of this project is what makes it stand out from other entries in the category.

Project team
Architect: AECOM SA.
Structural engineer: AECOM SA.
Main contractor: Stefanutti Stocks.
Project manager: AECOM SA.
Structural steel detailer: Cadcon.
Steelwork contractor: Cadcon.
Steel erector: Cadcon.
Quantity surveyor: AECOM SA.
Cladding manufacturer: Global Roofing Solutions.
Cladding supplier: Global Roofing Solutions.
Cladding contractor: Global Roofing Solutions (Botswana).
Nominator: Global Roofing Solutions.

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ASTPM tubular and architectural categories winner: Time Square Globe Bar and Casino Arch

Winner of two categories, the Time Square Globe Bar and Casino Arch project entailed the fabrication and erection of a curved plate for the main entrance arch, with the suspended tubular sphere for the Globe Bar with prism-shaped glass panels. Steel was chosen because of the fact that complex-shaped curve could not be achieved in concrete in the short space of time.

The arch is a composite steel and concrete structure with re-bar fitted during the fabrication process. It was fabricated in the biggest possible elements and erected using a 220 ton crane on a suspended fully propped slab, while lifts were taking place. Once site welded, concrete was pumped inside the plate arch using specially designed concrete slurry. The main and sub-contractors coordinated a full system of back propping and stripping to accommodate client budgets.

The Globe Bar was fully constructed offsite to get the geometry 100% correct. It was then divided into transportable units and the segments were bolted and welded on site. A sacrificial inner structure of I-beams was constructed and the external frame of the globe was pre-assembled on the inner frame to get the geometry correct and ensure the fit of glass panels. Mobile cranes and tower cranes were used to suspend the globe off the main arch legs, after which the last capping was installed.

This project is a good example of how technology and great workmanship have come together to provide an impressive structure.

Project team
Client/developer: Sun International.
Architect: LYT Architecture.
Structural engineer: Consultauri Design, WSP Structural Engineers.
Main contractor: WBHO.
Project manager: Proman.
Structural steel detailer: Bekker Steel, DN Design.
Steelwork contractor: Cadcon.
Steel erector: On Par Erectors.
Quantity surveyor: MLC Quantity Surveyors.
Cladding contractor: Facade Solutions.
Corrosion protection: Dram Industrial Painting Contractors.
Nominator: Cadcon.

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Commercial category winner: CTICC East

The east extension of the Cape Town International Convention Centre involved two new convention halls, a large concourse area and meeting rooms. Steelwork was the only practical solution for the large spans carrying very heavy loads on this project, although numerous other options were considered.

The second floor hall of 5 000m² is essentially supported by only four internal columns that carry a design live load of 750kg/m² in addition to dead loads. A system of deep primary and secondary girders, and tertiary beams supporting Bond-Dek cladding, was selected.

The roof structure over the upper hall comprises a column-free space of 5 000m². Due to architectural requirements, only two girders were permitted to span the short direction, with secondary girders spanning the long direction of the hall and rafters above.

The concourse and meeting pod structure comprises a vertical structure for the support of the 22m-high curtain wall, a composite roof structure over the meeting pods and part of the concourse, and a saw-tooth roof structure supporting insulated panels and glazing orientated towards the south.

Due to space constraints, the mobile mill had to be hoisted by crane onto a scaffold tower built next to the roof so that the sheets could be rolled directly onto the roof.

The connection between steel and concrete elements was particularly challenging, especially where forces were very high. Cast-in plates were used as much as possible, some weighing as much as 1 000kg. Steel connections in girders were also carefully workshopped to transfer the massive internal forces, while not being too difficult to assemble on site.

Project team
Client/developer: CTICC.
Architect: Convention Architects – a joint venture between Makeka Design Lab, SVA International and VDMMA.
Structural engineer: Sutherland.
Main contractor: Aveng Grinaker-LTA.
Project manager: Target Projects.
Steelwork contractor: Anchor Steel Projects.
Quantity surveyor: Mbatha, Walters & Simpson.
Cladding manufacturer: Bluescope Steel.
Cladding supplier: Macsteel.
Cladding contractor: Scheltema and Company.
Nominator: Sutherland.

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Safintra factory and warehouse category winner: 265 Sydney Road

Previously two buildings with low ceilings, the old Dunlop factory, which is situated close to Durban port operations, was redeveloped into a modern user-friendly facility with yard spaces lending themselves to high, large-span warehouses suitable for a wide range of tenants.

Structural framing for the large span (120m) warehouses includes lattice trusses with spine girders and internal columns to optimise clear areas and spans for tenant usage. Special considerations included erection of the frames and consideration of truss behaviour in sections during the rigging process. A big challenge was trying to get the roof sheets rolled onsite and then lifting and installing them 160m across the roof, especially in the wind.

Today, the facility has been transformed in a way that maximises space for its tenants, having only 18 steel columns as opposed to the over 70 columns of before and eaves heights of 12m instead of 4,5m.

Project team
Client/developer: JT Ross.
Architect: Peter Ries Architects.
Structural engineer: Cousins Steel International.
Main contractor: Rubro Building.
Project manager: JT Ross.
Structural steel detailer: Cousins Steel International.
Steelwork contractor and steel erector: Cousins Steel International.
Quantity surveyor: MLC Quantity Surveyors.
Cladding manufacturer: Safal Steel.
Cladding supplier: Global Roofing Solutions.
Cladding contractor: Cousins Steel International.
Corrosion protection: Insimbi Coatings, Voight & Willecke.
Nominator: Cousins Steel International.

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Steel Awards 2018 opens for project nominations on 1 November 2017. Any projects containing structural steel, completed in the 2017 calendar year, are eligible for submission. Entries close on 31 March 2018. For more information, contact Denise Sherman at the SAISC on denise@saisc.co.za or 011 726 6111.

Full thanks and acknowledgment are given to the Southern African Institute of Steel Construction for the information given to write this article and the photos supplied.

Photos courtesy of the SAISC