Friction Coefficient in Bridge Sliding Bearings

The paper gives an overview of the behaviour of polytetrafluoroethylene, or PTFE, used as main sliding surface in bridge bearings, focusing in particular on the friction coefficient in service conditions and the related influence of contact pressure. The two worldwide most popular codes on bridge bearings, the North-American Load Factor and Resistance Design Bridge Construction Specifications by American Association of State Highway and Transportation Officials, or AASHTO LFRD, and the European Norm 1337 give prescriptions for design and assessment regarding such aspects. The differences in materials and operations between the codes derive from different approaches followed for their development, more empirical and based upon historical data and manufacturers’ experience for AASHTO LFRD Specifications, and more supported on specific research data and experimental assessment for EN 1337.