連層耐震壁付鉄筋コンクリート架構の履歴性状に及ぼす基礎浮上りの影響

Abstract

When building structures with shear walls are subjected to an earthquake motion, it is con-sidered that the shear walls share most of the lateral force. As the results, the high overturningmoment at the basement may cause the shear wall to rotate with the separation between a foot-ing and the ground surface. And it is considered that the interactive behavior of the up-liftingshear wall and flexural frame system connected by boundary beams may cause the changes ofthe lateral stiffness of total frames and the shear force ratio of shear wall to attatched frames.In this paper, we examine the mechanical and dynamical characteristics of the reinforcedconcrete frames with shear wall considering up-lift of footing by using a shaking table.As for the dynamic test, the wave form of N-S component of Imperial Valley Earthquakerecorded at El Centro in 1940 was chosen for the input excitation. And the damage of theshear walls and the boundary beams by the up-lifting were examined and compared with theresults of static tests.The results of parametric analysis on the effects of up-lifting of a foundation and the stiff-ness ratio of shear wall to boundary beams are also presented in this paper.