MECHANICAL CHARACTERISTICS OF HIGH DAMPING RUBBER BEARINGS BY DYNAMIC LOADING TESTS UNDER THE LOW TEMPERATURE ENVIRONMENT

Abstract

 This study discusses the mechanical characteristics of high damping rubber bearings (HDRBs) by dynamic loading tests under the low temperature environment. Fundamental cyclic loading tests at different temperatures are conducted using 2 types of HDRBs (HDR-S and HDReX) and a natural rubber bearing (NR). In these tests, 175% shear strain of rubber thickness are given by loading facility in cold room. Equivalent stiffness of all specimens increase under low temperature and its ratio depends on type of rubber. Specially equivalent stiffness of HDR-S is significantly larger than other types because of its material characteristic. Internal temperatures of rubber bearings have linear relationship with energy loss. Gradients of the linear functions also depend on rubber type and ambient temperature. In cyclic loading tests under allowable design displacement (250%), the rate of change of the equivalent stiffness and energy loss of HDR-S significantly increase specially in −30°C. Finally, all specimens do not break under cyclic loading test of 120% allowable design displacement under any temperature cases.