This is a state-of-the-art report on precedures for design, fabrication, construction, and maintenance of bridge bearings. Performance records for currently used expansion devices are reviewed. The sliding device includes lubricants between surfaces, lead sheets between plates, self lubricated bronze plates, and polytetrafluoroethylene (TFE) sliding on stainless steel. Rolling devices, such as roller nests, larger rollers, single rollers, segmental rockers, and pinned rockers are examined. Linkage devices are used between girder where no movement is to be transmitted. Elastomeric bearing pads are quite successful, they have no moving parts to freeze, nothing to corrode, and have little or no maintenance requirements. Routine maintenance of bridge bearings should be directed towards keeping the bearings clean and free of water, salt, and debris. Recommendations include designing a bridge with a few movable bearings as possible; bearings should be designed to require a minimum of maintenance; provisions should be made so that the bridge may be jacked up and the bearings adjusted or replaced; material quality is important in elastomeric bearings; inspection of bridge bearings should be included as part of the regular bridge inspection program.
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