水平及び鉛直荷重を受ける改良9Cr-1Mo鋼製円筒容器の座屈評価法に関する研究

（その2：繰返し負荷した鉛直荷重や，軸圧縮，曲げ，せん断座屈の相互作用が座屈荷重に及ぼす影響について）

抄録

Buckling evaluation methods capable of evaluating elasto-plastic buckling under axial compression, bending, and shear loads are required for cylindrical vessels of FBR (Fast Breeder Reactor) to cope with thinning due to the increase in diameter, adaption of new materials and application to the seismic isolation design due to the increase in the design basis earthquake ground motion. So, buckling evaluation methods corresponding to the above condition are being studied. In this study, in order to examine the applicability of the new evaluation method, several buckling tests and FE analyses were carried out on a new material (Modified 9Cr-1Mo steel). The buckling mode and strength data in the load region where the interaction of axial compression, bending and shear buckling could occur, and the effect of repeated vertical load under a constant horizontal load were examined through the series of tests. As a result, it was confirmed that the evaluation by the proposed formula was conservative for the buckling load of the test. In addition, buckling strength evaluated by elasto-plastic buckling analysis had good accuracy compared to each test result by considering stress – strain relationship and imperfection of test vessel.