高加速度振動台実験に基づく鉄筋コンクリート板の動特性評価

摘要

It is essential to accurately grasp the seismic performance of building after severe earthquakes. To realize the quick inspection, research on Structural Health Monitoring (SHM) based on the evaluation of vibration characteristics has been actively conducted as a method for evaluating the structural integrity of buildings. It has been frequently reported the phenomenon of stiffness decrease from the seismic observations such as the 2011off the Pacific coast of Tohoku Earthquake or full scale shaking table tests. However, the mechanisms of decreases in the natural frequency and stiffness of the reinforced concrete shear wall have not been clarified yet. From the viewpoint of structural soundness assessment, clarification of stiffness decrease phenomenon after experiencing elastic response is required. To find out the mechanism of the stiffness decrease phenomenon of the reinforced concrete shear wall, we conduct three types of shaking table tests against the reinforced concrete plate simulated shear wall, and discuss the relationship between earthquake experience and stiffiiess decrease for in-plate bending deformation.%本研究では，RC造耐震壁の剛性低下現象やその速度依存等の知 見を得るために，RC板試験体に対しA，B,Cの3種類の振動台実験 を行った。A試験は高加速度の10.6Hz加振，B試験は通常の加速度 で10.6Hz加振，C試験は通常の加速度で2.12Hz加振であり，重錘 質量を調整することで試験体に入力する慣性力は等価になるよう にした。得られた知見を以下に列挙する。