Amplification in Mechanical Properties of a Lead Rubber Bearing for Various Exposure Times to Low Temperature

In this paper, new formulations to predict the change in mechanical properties, namely, post-yield stiffness and characteristic strength of lead rubber bearings (LRBs) at low ambient temperatures, are proposed based on test results. Proposed consider not only effect temperature but also exposure time temperature. Accordingly, a full-scale LRB was tested dynamically after being conditioned temperatures −20, −10, 0, 20 °C for 3, 6, 24 h. During displacement-controlled cyclic tests, various levels shear strain were applied isolator with loading frequencies 0.1 Hz 0.5 Hz. Then, force-displacement curves recorded, corresponding amplifications its hysteretic properties noted. The accuracy existing equations estimate amount amplification evaluated through experimental It found that formulas do represent characteristics temperatures. On other hand, result highly accurate estimations different times.