Design for Dynamic Effects in Long Span Footbridges

Clients are requiring longer spans for footbridges and cycle bridges. The paper follows a number of case histories of recent long-span footbridges. Four dynamic effects are identified which need to be considered by designers and each is discussed. Some of the design criteria are soft, in the sense that they are governed by human issues. The author makes a plea that these issues are not over-specified because the economic feasibility of longer spans may be at risk. There are some general comments on the likely form of future designs.