Mechanical behavior prediction and design limits for annular rubber bearings under compression: A theoretical study

The absence of both theoretical predictions regarding mechanical behavior and associated design limits has, to some extent, constrained the engineering application of annular thick rubber bearings, despite their various advantages. This work aims to develop a concise and precise approximate analytical solution to predict the mechanical behavior of annular rubber bearings under compression and to establish design limits, ultimately extending current standards to thick rubber bearings. The rigorous analytical solutions for the displacement component were derived by transforming the Navier displacement formulation into four distinct boundary-value problems. After calibration and simplification, the approximate analytical solution for displacement, strain and stress component, expressed using elementary functions and possessing clear physical interpretations, was derived. These solutions exhibit high accuracy in predicting the mechanical behavior of rubber bearings under compression, as verified by numerical simulations and existing literature. This study offers not only reliable predictive formulas for the mechanical behavior of annular rubber bearings, but also establishes relevant design limits, mainly including the max. local shear strain of rubber layer and the allowable compressive stress under service load, and the yield criteria for reinforcing steel plate, which may inform future design specifications.