クリープ変形を伴う免震建物の風応答性状に関する研究

Abstract

This study proposes analytical methods for determining wind responses of base-isolated high-rise buildings with creep deflection and clarifies characteristics of their modal forces and responses. The following results are derived. Modal forces on a base-isolated building are calculated easily by multiplying those on a conventional building with a linear mode shape function by the proposed mode shape correction factor. It is shown that the proposed methods for determining wind responses of base-isolated high-rise buildings with creep deflection are appropriate. Creep deflections are insensitive to fluctuating wind forces, so creep deflections and wind responses can be calculated separately. Shifts of the mean wind response of a base-isolated building due to plastic characteristics of isolation devices occur, but they behave almost elastically in the along-wind direction. However, the isolation layer moves inelastically in the across-wind and torsional directions. The standard deviation response calculated from the wind force for a certain direction is equal to or greater than that derived from 3 components of wind forces simultaneously. However, the mean response considering the former is smaller than that considering with the latter.