 Contact Artefacts | MenuHomeUpfront Now Up Books Towns Structures People Firms Lexicon | Steve Biko Bridge MURRAY and STEWART: Contractor CHRISTIANI and NIELSEN: Contractor |  | ||||||
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Click to view map Coordinates: | Originally John Vorster Bridge. The consulting engineers for the bridge project were Zakzrewski + Associates (Inc). (ZAI) The initial design and tender was for a conventional bridge which would have required temporary staging to support the deck while casting. Alternative designs were however allowed and the successful tender was that of a consortium of Murray & Stewart (Border) and Christiani and Nielsen (Pty) Ltd of Cape Town. The consortium was known as Murray – Christiani and their alternative design was for a balanced free cantilever bridge which offered a considerable cost saving. The detail structural design was undertaken by a Dutch Engineering consultancy which specialised in this type of bridge. The assessment of their design - on behalf of ZAI - was completed by a Swiss consulting firm. On 22 September 1973 the Daily Dispatch published a photograph recording the formal handover of the plans to the contractor. The caption to the photograph noted the following names: Councillor B. Kipling, Chairman of the Portfolio of Works, Mr. Edwards, Senior Engineer Murray and Stewart, Mr E. Howard, Project Engineer, Mr R. L. de Lange, Mayor of East London, Mr P. Lundhus, Site Agent and Mr C. Elliott, Director of Murray and Stewart. A photograph of Mr Clem Gerraty (Murray + Christiani's Site Manager) was also included. ZAI's resident engineer was Cedric Barker (deceased) who later joined BCM. Enrico Contardo was a Junior Engineer (recently graduated) with Murray & Stewart. A high strength, two-pack, imported epoxy adhesive was applied between the matching precast concrete bridge segments to ensure a durable seal and structural continuity. The seven-strand stressing cables were inserted through ducts in the precast bridge segments and were then post tensioned. The cable ducts were grouted up after post tensioning was complete. The contractors on site used the Swiss made Wild T2 High Accuracy theodolite that could read to a single second of an arc (1/3600 of a degree) for resections and triangulations. Once the bridge centre lines and off-sets were calculated and setting-out points had been established, the Wild T16 was used for ongoing alignment checks. The Mayoral Minutes of East London of 1978 mention that the final cost of the bridge was R4.4 million. References: Description of construction techniques and surveying provided by Wessels Frank, April 2020. Glenn Hartwig of the East London Public Library, Reference Section provided scanned copies of the articles in the Daily Dispatch. (William MARTINSON, May 2019) Books that reference Steve Biko Bridge
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