不確定な構造特性を有する免震建物のロバスト性評価のための地震時応答限界解析

摘要

An efficient methodology is presented to evaluate the robustness (variability of response) of an uncertain base-isolated building. While a basic assumption of "inclusion monotonic" is introduced in usual interval analysis, the possibility is taken into account of occurrence of the extreme value of the objective function in an inner feasible domain of the interval parameters. It is shown that the critical combination of the structural parameters can be derived explicitly so as to maximize the approximate objective function by 2nd-order Taylor series expansion. The URP (Updated Reference-Point) method is proposed to obtain such critical combination of structural parameters. In order to investigate the validity of the proposed robustness evaluation methodologies, numerical analyses are conducted for 20-storey base-isolated building models with natural rubber isolators and passive dampers. By comparing the results with the exact solution and those by other conventional methods, it is shown that the URP method can provide a more accurate evaluation of response bounds without hard computational effort.%増大する地震動レベルに対して高層建物や大規模構造物の設計を考える上で，免震技術や制振技術は不可欠なものとなりつつある。免震技術や制振技術を用いて構造物の安全性を高めるには，免震装置や制振装置を含めた構造物の特性を適切にモデル化した上で，期待される応答低減効果を高精度に評価する必要がある。