Engineering - Steel bearings
Line bearing (LB)
Flat and cylindrical line contact configuration absorbs direct and rotational movement
Line bearings support vertical loads using a combination of a cylindrical face on the lower shoe and a flat face on the upper shoe to provide line contact. The cylindrical face also tracks rotation associated with flexure in girders.
Practical and economical
Line bearings are structurally very simple, consisting solely of the upper and lower shoes. Vertical load is absorbed through the linear contact between the flat upper face and the cylindrical lower face. Line bearings are cheap, compact and easy to install.
Line bearings are ideal for small bridges and those with relatively short spans. Increasingly they are retrofitted to existing bridges for reinforcement.