中央コアから側柱までのスパン16m~20m が好まれる日本の超高層建物では，アウトリガートラスの曲げ剛性が海外より最大約20%まで劣化してしまい， ダンパーの接合部として十分な剛性を確保できないため，ダンパー付アウトリガー構造は国内では殆ど普及していません。これに対してエネルギー吸収効果を自己増幅できる同調粘性マスダンパー(Tuned Viscous Mass Damper, TVMD)は，曲げ剛性の確保が難しい日本のダンパー付アウトリガー構造の抜本的な解決策になると考えられており，都内超高層建物の耐震改修にも使用されていますが，その実現可能性には未だ不明な点が多いです。そこで本研究では，典型的な日本の中央コア型超高層建物を対象に，様々な質量比と配置を有するTVMD の応答制御効果を比較し，さらに現実的なケースを対象に具体的な納まりを設計し，導入費用を試算して実現可能性を評価しました。日建設計との共同研究成果です。やっと日本に適したダンパー付アウトリガー構造の解が得られて嬉しいです。論文はこちら
The damped outrigger system is known to efficiently provide additional damping in tall buildings. However, particularly for tall buildings in Japan, the outrigger truss from the center core to the exterior columns need to span distances of more than 16m. This is because Japanese developers prefer real estate that may maximize the leasable floor. This Japanese culture increases the flexural stiffness demand on the outrigger that leads to larger truss depths making the damped outrigger system inefficient, resulting that the damped outrigger is rarely adopted in Japan. To overcome this problem, following a successful example (available at https://xtech.nikkei.com/atcl/nxt/mag/na/18/00131/030300003/) of seismic retrofit of Japanese tall building, we proposed a novel damped outrigger system with tuned viscous mass dampers (TVMDs, a type of inerter). In the proposed system, the flexible outrigger truss is used as the the tuned spring for the viscous mass damper. In this paper, a series of complex modal analysis and nonlinear response history analysis for a typical Japanese tall building with a center core was performed to investigate the seismic response reduction effect. Moreover, the structural detail was designed to estimate the cost and cost performance index, and the feasibility of the TVMD damped outrigger system was strictly discussed.