1996 年 45 巻 9 号 p. 1042-1047
This paper presents the results of tests made to study the effects of accumulative damage, column height, and longitudinal steel ratio on the vibrating properties of R/C columns. The random waves acceleration recorded by actual earthquakes in Japan-Nihonkaichubu-were induced on the specimens. Two kinds of dynamic tests were carried out. The column specimens which have three kinds of height and two kinds of longitudinal steel ratio were tested. From the test results2), the changes in vibrating properties were examined and compared with the last test results. It was found that the effect of accumulative damage on the damping factor was larger than that on the natural frequency and the dynamic damage in the natural frequency was mainly affected by steel yielding. Furthermore, the effects of column height on the natural frequency and damping factor agreed well with the expectation, and the effect of longitudinal steel ratio was not so significant.