Studies on Seismic Design of Concrete Structures

这位首席研究员提出了混凝土结构抗震设计的概念，其中混凝土结构的设计不仅要使其在地震中安全，而且要满足地震后的使用要求。日本土木工程师学会的《混凝土标准规范》采用了这一概念。鉴于拟动力加载试验是研究钢筋混凝土柱非弹性性能最有效的工具，首先研制了一套基于PC机和执行器相结合的加载系统。利用该系统对钢筋混凝土柱试件和钢筋混凝土刚架试件在实际地震作用下的弹塑性反应特性进行了研究。将计算结果与原计算机程序计算的解析值进行了比较。静力反向循环加载试验验证了JSCE规范中混凝土结构损伤等级分类的合理性。拟动力试验验证了各损伤等级设计值的合理性。对沉管钢筋混凝土隧道的抗震性能和设计进行了研究，发现隧道构件的柔性接缝对地震作用是有效的。

The head investigator proposed a concept of seismic design of concrete structures in which concrete structures should be designed not only to be safe during earthquakes but also to fulfill serviceability after the earthquakes. This concept was adopted in the Standard Specification of Concrete of the Japan Society of Civil Engineers (JSCE). This study intends to confirm the appropriateness of the concept and to develop the design method.Since pseudo-dynamic loading test was the most useful tool to investigate inelastic behavior of reinforced concrete columns, a loading system using personal computer combined with actuator was developed successfully at first. By using this system, reinforced concrete column specimens and reinforced concrete rigid frame specimens were studied to obtain inelastic response characteristics under actual earthquake motions. The results were compared with the analytical values which were calculated by means of the originated computer program. Satisfactory coincidence was shown in both values.Static reversal cyclic loading tests clarified the appropriateness of the classification of the level of damage in concrete structures specified in the specification of JSCE. Pseudo-dynamic test confirmed the appropriateness of the design values specified for each damage level.Studies on seismic behavior and design of immersed reinforced concrete tunnels were carried out and flexible joints of tunnel elemants were found to be effective against earthquake motions.