Expansion joints for ever longer, lighter bridges

The drive to construct bridges with ever longer spans, using ever less materials and resources, presents challenges for the suppliers of key bridge components such as the expansion joints which must provide a continuous driving surface at the ends of the structure’s deck. Not only will the longitudinal movement range of the joints increase, but the flexibility of the joint to accommodate the more frequent and unpredictable movements of a less robust bridge deck must also be ensured. Durability also becomes a more critical consideration as a result of the increased movements and reduced robustness, and the design of the joints, and the materials used in their fabrication, must reflect this. It is important that bridge designers and constructors have an understanding of these issues, and of the implications of their designs for the expansion joints whose performance will be a significant factor in the constructability and life-cycle costs of the bridge.