Sensitivity analysis on mechanical characteristics of lead-core steel-reinforced elastomeric bearings under cyclic loading

This research conducts a sensitivity analysis on the mechanical properties of lead core rubber bearings (LCRBs). Here, the input variables include: number of rubber layers, lead core radius and lead core material properties. A full factorial numerical experiment is designed and the hysteretic behaviour of a total of 81 LCRBs with varying parameters is captured through numerical simulation. The material models used in those models were first validated with experimental results from published literature. Operational characteristics of the studied bearings include: the vertical and horizontal stiffness, and the equivalent viscous damping ratio. An analysis of variances is then conducted in order to quantitatively express the effectiveness of each parameter. Among the three considered input variables, the lead core radius is the most dominant parameter in affecting LCRBs' performance, whereas the number of rubber layers has the least contribution. It is observed that the lead core influences bearing's vertical stiffness the most, compared to other input variables.