BASE ISOLATED STRUCTURE, AND BASE ISOLATION DEVICE FOR USE IN THE BASE ISOLATED STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide a base solation technique which allows base isolation devices to dispersively bear an unexpectedly large horizontal force if the horizontal force is imposed on a building and the base isolation devices each undergo abnormal displacement falling out of a base isolation region, and facilitates recovery of an upper structure of the building to its original position after cancellation of the horizontal force. SOLUTION: Each base isolation device employs an abnormal displacement preventing means to cope with the abnormal displacement falling out of the base isolation region occurring due to an unexpected external force. The abnormal displacement preventing means accommodates relative displacement of an upper bearing member 5 to a lower bearing member, and at the same time prevents the abnormal displacement falling out of the base isolation region, by upward displacement of the upper bearing member 5 generated by rolling of a ball body 6 according to the displacement. Thus by virtue of cooperative operation of the abnormal displacement preventing means of the respective base isolation devices, the unexpected external force caused by wind etc. is dispersively borne by the base isolation devices. COPYRIGHT: (C)2007,JPO&INPIT