Assessment of heat generation in sliding pendulum isolators

Issues related to heat generation in sliding pendulum isolators used as seismic dampers are approached by developing a method for studying the heat state of seismic isolation units in computer analyses. A finite element model of pendulum isolator is created and the generation of frictional heat is reproduced by introducing a heat source located between the moving surfaces, with specific power calculated upon friction coefficient, contact pressure and velocity; the influence of the current surface temperature on the coefficient of friction is also accounted for by means of a custom iterative subroutine. The model provides as the output the temperature field within the isolator over the whole duration of the seismic excitation. Experiments carried out on real scale isolators confirm the reliability of model predictions. The procedure can be a useful design tool for carrying out computational investigations within a wide range of loading and material parameters.