Abstract
東北地方太平洋沖地震に伴う津波により，多くの土木・建築構造物が崩壊した．今後危惧されている巨大津波が発生する前に，沿岸地域の防災・減災技術の再検討を行なう必要性が高まっている．このような実状を踏まえて，現在，迅速な避難を困難とする人々の一時的な避難のための施設として，津波避難ビルの選定・指定が進められている．構造物に作用する津波の影響は，津波そのものの流体力に加え，漂流物の衝突，基礎地盤の洗掘，あるいは浮力の影響などを複合的に判断し安全性を議論することが望ましい．本研究では，その第一段階として，避難ビルに作用する津波流体力の評価のみに焦点をあてた基礎検討を行った．数値解析より得られた結果と経験的な既往の設計式と比較を通して，設計時に数値解析を併用する必要性と有効性を議論した．
The tsunami caused by the great east Japan earthquake lead to collapse infrastructures including bridge and breakwater. It is important to reconsider disaster prevention and mitigation techniques towards next millennium tsunami. Currently, most of local governments in Japan are promoting the selection and specification of tsunami refuge buildings for people who live in the difficult area to evacuate within the limited time. However it's difficult to settle the design code of tsunami refuge building because there are so many incertitude accident during tsunami related to water induced impact force, buoyancy force, tumble of the building and so on. Numerical simulation by a particle method has been conducted for the evaluation of tsunami fluid force acting on tsunami refuge building as a first step. Finally, efficiency and adequacy of numerical simulation in the design of tsunami fluid force has been discussed by comparing with the current design code in Japan.