A novel friction model for steel-polymer interfaces in sliding seismic isolation bearings

Experiments have shown that the coefficient of friction in steel-polymer interfaces is influenced by several interacting parameters, making it difficult to accurately model the instantaneously varying coefficient of friction in sliding seismic isolation bearings. A new model to characterize the variation of the coefficient of friction in sliding seismic isolation bearings in which a thermoplastic slides relative to a steel surface is presented. The model takes into account the variation in the coefficient of friction produced by changes in sliding velocity, normal pressure, and stick-slip phenomena, as well as degradation due to frictional heating. In particular, the model takes into account the differences in behavior during reversing and nonreversing stick-slip transitions. It is shown that the proposed model is able to reproduce very well experimental results of friction tests using various steel-polymer interfaces.