Steel use in offsite construction

The Hercilio Luz suspension bridge (see Fig 1) in Southern Brazil was designed by D. B. Steinman and opened in 1926 but has been closed to traffic since 1983 following discovery of a broken eye-bar link. The riveted steel superstructure is currently being refurbished as part of a programme intended to return it to full operation by the end of the year 2010. As a consequence of the structure's national heritage status, technical issues and the local technology and labour force environment, the connections are being made using hotdriven rivets with diameters ranging from 19 to 25mm (3/4in. to 1in.) and grip lengths very often up to 100mm. This paper explains the decisions behind the choice of riveting and describes how the riveting process is executed, monitored and controlled. A brief discussion is also included on the design of riveted connections. The revival of riveting is proposed as a viable connection technique for the refurbishment of similar historic structures. Richard H. Lamb BSc (Hons), MSc, CEng, MIStructE Structural Engineer, Prosul-Concremat Consortium