Evolution of suspension bridges

Abstract

The suspension of bridges by cables is one of the oldest methods for spanning relative longs bridge spans with no intermediary supports. It is utterly simple in its basic concept and offers excellent opportunities for even very long spans.

The paper describes the evolution from medium span suspension bridges with simple technology over more and more sophisticated technologies to the modern suspension bridge comprising many new innovations for the continuous aerodynamic bridge deck and internal corrosion protection by dehumidification with wind flow improving devices, wind screening with no adverse effects on aerodynamic stability, hydraulic damping and buffer devices for deflection control and wear reduction of expansion joints and bearings as well as advanced anchorage structures with proper consideration of soil/structure interaction.

Future development with review of the potential of new materials like carbon fibres and other new technologies with aerodynamically driven active control systems, which would allow extreme spans of 3- 5.000 m suitable for Messina Strait and Strait of Gibraltar is also presented.