Eiji Takaoka

SHAKING TABLE TESTS ON THE ULTIMATE BEHAVIOR OF SLENDER BASE-ISOLATED BUILDINGS SUPPORTED BY LAMINATED RUBBER BEARINGS

This paper describes the results of shaking table tests on a slender base-isolated building model supported by four laminated rubber bearings to clarify the ultimate behavior when bearing fracture occurs. The results of the tests indicate that the ultimate behavior of the base-isolated building is roughly classified into two types; one is caused by buckling fracture of the bearing, and the other is a result of tensile fracture of the bearing. In the buckling type, one of the standards for judging the occurrence of buckling fracture is that the lateral deformation exceeds the value corresponding to the diameter of the bearing, and the aspect ratio of the building does not have much effect on the ultimate behavior. In the tensile type, tensile deformation becomes higher with an increase in aspect ratio, and the ultimate input level does not decrease. The building has a safety margin to fracture even if the aspect ratio becomes larger.