抄録
When a tall seismic isolated building is suffering a big earthquake, large tensile forces may occur at the multi-layer rubber bearings due to the large overturning moment. Tensile stress is critical design problem for such rubber bearings. To avoid such large tensile forces at the bearings, the design idea allowing uplifting at bearings may be preferable for the tall seismic isolated buildings. However, very few studies have made about the nonlinear behaviours of such seismic isolated buildings considering the foundation vertical stiffness. The shaking table test is carried out to investigate the nonlinear dynamic response of seismic isolated buildings that allow the uplifting around the rubber bearings, considering the vertical elastic stiffness of the foundation. From the results getting from the tests, the effect of seismic isolation would be guaranteed even if some bearings step up during earthquakes.
