抄録
Evaluation of bi-directional characteristics of base-isolation devices is a very important issue for base-isolated structures. The present paper focused on structural behavior and deformation capacity of U-shaped steel dampers under random bi-directional dynamic loadings. The major findings obtained from the test are summarized as follows: (1) the index Jc proposed in the previous paper can evaluate the limitation of cumulative torsion until contact with connections under random bi-directional loadings; (2) damage evaluation with two indices D2 and Jc leads to a conservative result under the random bi-directional loadings; (3) in addition to this, cumulative deformation due to the different orbits brings more conservative evaluation.
