Architect and Builder Magazine South Africa Dec 2017 / Jan 2018 - Page 94

2017 STEEL AWARDS T he highlight of the structural steel industry calendar, the 36th Annual Steel Awards hosted by the Southern African Institute of Steel Construction in partnership with Aveng Trident Steel, took place in September in Johannesburg, Cape Town and Kwazulu Natal concurrently. Attended by close to 900 people the event showcased projects completed in the previous year that demonstrated excellence in the use of structural steel. 56 Projects were entered into this year’s awards. Sponsors for the event were: Main - Aveng Trident Steel, Popular Vote Feature - Macsteel, Photo Competition - Cadex Systems SA, Tubular category - The Association of Steel Tube and Pipe Manufacturers, Light steel frame building category - MiTek Industries South Africa, Metal Cladding Category - Global Roofing Solutions, Factory and Warehouse category - Safintra, and Innovation Category Safal Steel. Partner Sponsors - ArcelorMittal SA, BSi Steel, NJR Steel and Stewarts and Lloyds. OVERALL AND INNOVATION CATEGORY WINNER BMW Rosslyn Roof Lift Building 50, known as the assembly building at BMW Rosslyn is about 60 years old and consisted of a low saw- toothed profile roof supported by numerous columns at close spacings. In 2018, BMW Rosslyn will produce the X3 model instead of the 3-Series and the latest assembly line technology necessitated that a 4100 m² portion of the current B50 structure be modified. The proposed system, H-EMS (Heavy Electric Monorail System), comprises overhead conveyors fixed to the roof, with height-adjustable hangers that carry the vehicles being assembled. The roof and column structure of the existing assembly building was inadequate for this purpose. The H-EMS system required a higher and stronger roof structure with fewer columns. 94 The Rosslyn Plant consists of only one final assembly line, and since the Plant is very compact and congested, the possibility of first erecting a new building adjacent to the existing Building 50 and thereafter demolishing the exiting was not an option. The only option therefore was to erect a new roof structure over the existing Building 50 whilst the assembly plant remained operational. The solution consisted of construction of an overhead working platform adjacent to the tower crane on the eastern end of the building. The platform had to be constructed slightly lower than the new roof level. The roof structure could then be constructed on the platform, one roof bay at time. As a parallel process, columns had to be installed on the foundations, penetrating through the existing roof. This work was performed 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 launched hydraulically – like an incremental bridge launch - and then the process could be repeated. Once the entire roof was in its final position, the installation of roof sheeting and vertical cladding could commence. The interface between the old (lower) and new (higher) roofs needed to be completed along the full perimeter of the new roof before the old roof could be demolished. The old roof was demolished during the December 2016/January 2017 shutdown and the rubble removed. Access could then be handed over to the H-EMS contractor to suspend the new assembly line equipment from the new roof. While some representatives at BMW were very appre- ciative but overwhelmed by the innovative concept that Steel Awards