三菱地所設計　YEARBOOK　2016

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Year Book 2016International Projectsサンシャイン60長周期地震動対策工事が完了Sunshine 60 Long-Period Ground Motion Retrofit Completed巨大地震が発生した際に予想される長周期地震動は超高層ビルに大きな影響をもたらすと考えられています。このためサンシャイン60では長周期地震動に対する安全性を高めるため、2014年3月より対策工事を実施してきました。当社と鹿島建設JVにて設計、工事監理を担当し、約２年半の工事期間を経て2016年8月に完了しました。補強計画は、ビル側面の避難バルコニー部に高性能オイルダンパーと鋼製弾塑性ダンパー、またコア部天井内の梁に当ビル用に新開発された変形制御ダンパーの合計３種類のダンパーを効果的に配置するもので、この補強工法は国内で初めての採用になります。本工事は建物共用部での施工が中心で、専有部への影響を最小限に抑えています。Ultra-high-rise buildings are thought to be strongly affected by long-period ground motion, one of the anticipated consequences of a major earthquake. To increase the safety of the Sunshine 60 tower against long-period ground motion, retrofit work was carried out by a joint venture between general contractor Kajima and Mitsubishi Jisho Sekkei, which was responsible for design and construction supervision. The work began in March 2014, and was completed in August 2016, after a construction period of about two and a half years.The retrofit installed three different types of dampers in an effective arrangement that was employed for the first time in Japan. High-performance oil dampers and elasto-plastic steel dampers were installed at emergency escape balconies at the side of the building, and deformation control dampers were installed on beams inside ceilings of the building core. The deformation control dampers were newly designed especially for this building.The construction work was carried out mainly in common areas of the building, with minimal disturbance of tenant areas.05034