Expansion joints for urban bridges – quiet, reliable and low-maintenance

The bridges that a city needs, and in particular its expansion joints, must be designed and fabricated to consider and satisfy a variety of other needs of the city and its inhabitants in addition to providing a simple trafficable route. In an urban setting, issues such as noise, reliability and ease of maintenance take on special significance, due to the increased importance of the structure and sensitivity of adjacent communities to noise, compared with a similar bridge in a rural setting.

Solutions to the challenges facing the suppliers of expansion joints for urban bridges are presented, including descriptions of the various types of “quiet” expansion joint available, and of ways in which existing or new joints can be made quieter. The importance of using high-quality and innovative materials, in particular for sliding components which are particularly susceptible to wear, is discussed. Use of such materials, in expansion joints which have been designed and tested for long life in demanding conditions, will minimise the need for maintenance and replacement work, thus reducing not only the cost of such works but also the effect of traffic disruption on the local population. Other design factors, such as consideration of seismic events, which if neglected could result in a city’s lifelines being cut at a time of great need, are also considered.