Sliding isolated structures. Experiments and mathematical modeling

A series of experiments on Teflon sliding bearings has been carried out for the purpose of developing a mathematical model of the frictional behavior of these bearings under conditions of interest in base isolation. Unfilled and glass filled Teflon at pressure of 1000, 2000, 3000, and 6500 psi and 20 in/sec. A mathematical model has been developed that is capable of reproducing the behavior observed in the laboratory. The developed model has been used in the analysis of sliding isolated structures with some interesting results. Sliding bearings designed at low bearing pressure exhibit high friction but also significant variation of friction with velocity of sliding. As such, base shears and base displacements in structures supported by low bearing pressure Teflon bearings are lower than in structures supported by high pressure bearings.