5. Support devices

The supporting devices play a direct role in the structure's operation. Placed between the deck and the supports, their role is to transmit the vertical actions due to the permanent load and operating loads (road or rail loads), and to allow rotational movements (effects of operating loads and deferred concrete deformations).

• There are three main families of support devices:

  • steel bearings specially designed for certain large metal bridges, but increasingly rare for reasons of cost and maintenance;

  • shrink-fit rubber bearings (figure 14 ), made up of a stack of elastomer plates and steel sheets (these are the...