ABSTRACT
Concrete bridges expand and contract with temperature changes, they shorten under the effects of concrete shrinkage and creep and they defl ect under the effect of applied loads, prestress and temperature gradients. The deck must be held in place when subjected to wind, seismic activity and to forces applied by the traffi c carried. If the deck is long, it may be necessary to divide it into several expansion lengths by intermediate joints. The articulation of a bridge may be defi ned as all the measures taken to hold it fi rmly in position while allowing it to change in length and width and to rotate at supports.
