Bridges expand and contract due to temperature changes. In larger structures expansion joints are required to accommodate the resulting movements between adjacent bridge deck spans or between the bridge deck and abutment. The joint must provide a suitable running surface for traffic crossing the expansion gap. Various types of joint are defined in the National Highways CD357, Bridge Expansion joints. The choice of the appropriate joint will depend on a number of factors, including the imposed loadings, anticipated movement, temperature range, deck shortening and rotation.

Further information may be obtained from the Bridge Joint Association (www.bridgejoints.org.uk)