Rapid Launching of the Howick Rail Bridge, South Africa

Late in 1992, road authorities in Natal, South Africa, invited tenders to upgrade a section of secondary main road through Howick. The contract was to include construction of a bridge through an existing rail embankment. As this double rail line joins Durban to Johannesburg and thus to the industrial heart of the country, it carries heavy and high value traffic. The rail authority therefore assigned a high cost to disruption of this traffic, as any delays would reduce their considerable income from these lines. A design was consequently postulated for the bridge which would enable it to be constructed with only two short interruptions to rail traffic of about 18 hours each. A tender based upon the author's alternative design for the bridge was accepted, however, which made it possible to complete the work with only a single interruption to rail traffic, lasting 24 hours.