Explicit nonlinear formulation of bridge bearings with the Mullins effect

Bearings for bridges, earthquake isolation bearings for buildings, and elements in vehicle suspensions may be made from one or more layers of rubberlike material between rigid steel plates to which the material is bonded. However, rubberlike materials are generally not purely elastic and when they are subjected to cyclic loading they exhibit stress-softening phenomenon widely known as the Mullins effect. Using a variational method, this paper develops novel explicit nonlinear forms of solution for axial deformation of bonded mounts that exhibit stress softening. The explicit formulae are simple to use for design purposes, and are consistent with expected behaviour.