Evaluation of shear modulus of high damping rubber bearings and lead rubber bearings during low-rate load reversals

Presented are two loading schemes proposed for evaluating the equivalent stiffness of Menshin devices against low rate loading developed due to the elongation and shrinkage of a bridge deck associated with the daily change of temperature. Although it is important for properly designing the Menshin devices against such deformation, it is generally difficult to evaluate it because the test requires a special loading facility which can produce the loading with extremely low frequency. Therefore the Extrapolation Method and the Relazation Method qre proposed for such purpose. The validity of the two methods is examined through the tests to two high damping rubber bearings and a lead rubber bearings.(AU)

Development of high damping rubber bearing for menshin bridges

This paper describes fundamental properties and dynamic loading test results of high damping rubber bearings for menshin bridges which habe been developed taking part in the joint research program between Public Works Research Institute (hereinafter called "PWRI") and the Yokohama Rubber Co., Ltd. (hereib=nafter called "YRC"). Through a series of tests perfomed, factors which significantly influence the properties of high damping rubber bearings became apparent. An effective damping ratio of 15

or over could be obtained under the assumed largest earthquake.(AU)