Basic Research on Vibration Control Building Structural System Including Uplift Mechanism

为了减少建筑物的地震破坏，人们提出了一些在地震中有意允许隆起的结构体系。这些体系可普遍应用于大宽高比的建筑，其中大多数只有单跨。而这些建筑物将在一侧的轴承周围完全隆起。另一方面，我们提出了“振动控制系统，包括隆起机制”，假设地震破坏的多跨建筑物，也可以减少，即使他们被允许部分，而不是全部隆起。本研究主要研究了建筑物上拔的方法和结构体系的抗震性能，主要研究成果如下：（1）消能机理阐明了允许建筑物整体上拔和部分上拔时的消能机理。（2）建筑物上抬的结构方法提出了一种利用屈服底板使建筑物上抬的结构方法。每个柱脚上都安装有屈服底板。在大型试验的基础上，明确了底板的恢复力特性。（3）有限元时程反应分析方法通过与试验结果的比较，说明了有限元时程反应分析方法对允许上拔建筑物的适用性，该方法能够分析底板的冲击效应和非线性特性。（4）结构体系的减震效果采用时程分析方法对结构体系的抗震性能进行了验证。揭示了它们的耗能机理。（5）允许上拔建筑物的模态分析为了更全面地了解允许上拔建筑物的地震反应特性，采用了模态分析方法。特别是高阶模态对结构动力特性的影响。

To reduce seismic damage of buildings, some structural systems which are intentionally allowed to uplift during an earthquake have been proposed. These systems can be generally applied to buildings with large aspect ratio, most of which has only single span. And these buildings will wholly uplift around the bearing on the one side. On the other hand, we propose ‘vibration control systems including uplift mechanism', assuming that seismic damage of buildings with multi-spans can be also reduced even if they are allowed to uplift partially, not wholly. In this research, we develop a method to make buildings uplift and examine seismic performance of the proposed structural systems.The achievements of this research are summarized as follows ;(1)Energy dissipation mechanismSeismic energy dissipation mechanism of buildings allowed to uplift wholly or partially were clarified.(2)Structural method to make buildings upliftA structural method to make buildings uplift using yielding base plates was proposed. The yielding base plates are attached at each column base. The restoring force characteristics of the base plates were cleared based on the large scale-tests.(3)FEM time history response analysis methodApplicability of FEM time history response analysis method, which can analyze impact effects and non-linear behavior of base plates particularly, to buildings allowed to uplift was shown comparing analysis results with past experimental results.(4)Seismic response reduction effects of proposed structural systemsSome case studies using a time history analysis method were carried out to verify seismic performance of the proposed systems. And their energy dissipation mechanism was shown.(5)Modal analysis on buildings allowed to upliftTo understand seismic response characteristics of buildings allowed to uplift more generally, a modal analysis method was applied. Especially, effects of higher modes to dynamic behavior of them were shown.