Three-Dimensional Macroscopic Model for Simulating Dynamic Behavior of Elastomeric Bearing Including Rotational Damping Effects

Damping effects are crucial for accurately simulating the dynamic behavior of elastomeric bearings under multiaxial excitations. Most existing macroscopic models only incorporate the horizontal and vertical damping effects through hysteresis models or viscous damping but neglect the rotational damping effects. Thus, the influence of rotational damping on the mechanical behavior of the bearing is still unknown. In this study, a new three-dimensional macroscopic model was developed to simulate the dynamic behavior of bearings under multiaxial excitations, and a new rotational hysteresis model was developed to incorporate rotational damping effects. The equations of force equilibrium and deformation compatibility were derived, followed by a suggestion of its numerical implementation. The robustness of the new model was validated through comparison with previous test results under extreme horizontal excitation and combined moderate and extreme horizontal and vertical excitations. The influence of rotational damping on the mechanical behavior of the bearing was investigated. The results indicate that the rotational damping effects contributed to the hysteresis enlargement under large horizontal displacements and mitigated the fluctuation in the hysteresis loops under vertical excitations. Neglecting rotational damping effects overestimates the horizontal displacement of the bearing. Moreover, a sensitivity analysis was carried out on the new rotational hysteresis model. The calibrated model parameters and experimental phenomena were cross-validated to confirm the rationality of the new model.