Experimental and Analytical Study on Multiaxial Hysteresis Behavior of High-Damping Rubber Bearings

Experimental and Analytical Study on Multiaxial Hysteresis Behavior of High-Damping Rubber Bearings

High-damping rubber(HDR) bearings have gradually become a commonly used type of seismic isolators worldwide. Because of the complex material compound, their actual hysteresis behavior is highly nonlinear and may not be very well represented by the existing bilinear approximation. In this study, first, a modified mathematical model is proposed for comprehensively characterizing the unilateral hysteresis behavior of HDR bearings under sinusoidal and triangular reversal loading. In addition to unilateral reversal loading tests, HDR bearings are tested with different non-proportional plane loading patterns, including circular and figure-eight orbits. It is found that under bilateral reversal loading, the torsional coupling effect is significant on the mechanical properties and hysteresis behavior of HDR bearings. Therefore, integrating the three-dimensional constitute law and the plane vector concept with the modified unilateral model, a further extended mathematical model for HDR bearings under non-proportional plane loading is developed. The accuracy and applicability of the modified and further extended mathematical models are verified through comparison with the test results.