This year marked the completion of the R200-million structural steel contract for one of South Africa’s largest steel fabricators, Genrec, a Murray & Roberts company, which constructed the new Sports Hall at the Khalifa sports city in Doha, Qatar. South Africa’s Murray & Roberts, through a joint venture with Consolidated Contractors International Company (CCIC), was awarded the contract in July 2003, and appointed Genrec in August 2003 to carry out all structural steel work related to the sports hall at the stadium, which will host the Asian Games next year. Genrec project manager Floris Brand describes the stadium as two offset semihemispherical shells of tubular steel-truss construction, fully sheeted, glazed and joined together by a central passage structure of fabricated steel girders and sections to form one large single hall. One of the semihemispherical structures houses a full-size indoor football field, change rooms, meeting rooms, seating for 5 000 spectators, an Olympic pool and diving pool, jacuzzi, warm-up pool, table-tennis area, and other associated facilities. The second semihemispherical structure houses an athletic track, fencing hall, multipurpose hall and a martial-arts area. The central part houses more change rooms, rest rooms, meet-ing rooms, the press and VIP areas, a fitness and health centre, shopping area and administration offices.

Brand reports that 2 800 t of steel, to the value of just under R50-million, was used for the central passage and roof purlins, and that it was sourced from South Africa. “The order was locally-manu- factured at Genrec’s 50 000 m2 premises in Wadeville, in Ger-miston, Gauteng, containerised and shipped to Doha, Qatar during the first half of 2004,” he says. Brand highlights that, owing to the pure size and scale of the tubular fabrication assemblies that were required for the semi-hemispherical shells, they had to be manufactured on site and a 6 500 m2 on-site fabrication facility was established for this purpose. “It was fully-equipped with portal cranes, CNC pipe-pro-filing machines to cut tubular steel, mobile jigs and welding equipment,” he says.

Challenges
Brand highlights the procurement of materials and logistics as two of the main challenges the project-management team had to overcome. The high-grade tubular steel was sourced from UK-based and Korean-based mills, while other steel materials, equipment and consumables were sourced from around the world.

The on-site fabrication of the tubular structures was also extremely challenging owing to the unique and complex nature of the three-dimensional assemb-lies required for the roofs, which had to be executed to the highest-quality standards and specifications. The on-site transportation and handling of these large assemblies within the limited space available required some intricate planning and erection methodologies. The impact of daily and sea-sonal temperature fluctuations on the steel had to be considered at all times, and especially during the depropping operation of the two main arches.

Approximately 800 t of steel had to be fabricated for the tem-porary support of the main arches and roof trusses until all of the shell-roof steelwork was in place. Thereafter, the main arches were depropped and the support steel-work removed. Restricted access, close inter-facing with other disciplines, and complex rigging and erection methods were part of everyday life.

Owing to the fast-track nature of the project, Genrec had to ship equipment from South Africa to Qatar in order to get the on-site fabrication facility operational in only three months. Genrec operations manager Gert Strydom says that the detailing and design of the project was extremely challenging, but that it was, at the same time, rewarding, considering the complexity of the technical obstacles encoun-tered.

“It evolved into a symphony of tubular and conventional arched steelwork, working in harmony with glass walls and sheeted roofing in an overall curved architectural design,” he says. The full 8 400 t of steel was locally detailed over a period of eight months, using the three-dimensional modelling-package, StruCad, from the UK-based AceCad. The company recently won the AceCad Worldwide StruCad drawing competition for the innovative design of the Khalifa Sports Hall, competing against more than 200 entries from over 30 countries around the world. At peak, the structural steel component of the project employed just under 1 000 workers, from 13 different nationalities. “About 500 people were employed on the manufacturing side and about 450 for the construction,” Brand says. To fulfil the total site-labour requirement, Genrec also per-formed on-site training and welder testing. Throughout the project, world-class safety standards were maintained and Brand says that the extreme heat conditions in the Middle East required that workers be kept well hydrated at all times.

Local market important
The South African steel fabricator has a longstanding presence in the Middle East and marketing manager Pravin Mooruth says that it is an exciting and growing market. The company was involved in a number of high-rise buildings, including the Burj-Al-Arab Hotel and the Emirates Towers, both in Dubai, and the Zayed cricket stadium, in Abu Dhabi. “But, being a local company, Genrec has a great interest in South Africa,” he says. The contract to export 2 800 t of steel from South Africa bene- fitted the local market by pro-viding opportunities for employ-ment. “The expertise gained in pro- jects outside the country’s bor-ders, is enhancing the local skills,” Brand adds. “We are loyal to the South African market but if there is a window of opportunity in another market or market segment, we will take it on,” Mooruth says.

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