1995 年 60 巻 478 号 p. 143-151
To control the failure mode of R/C column during a strong earthquake, the flexual strength of the critical section and the shear strength of the column should be accurately estimated. Antisymmetric eccentric compression tests and symmetric eccentric compression tests of R/C columns were carried out. The compressive strength of the concrete used in this experimental study ranged from about 300kg/cm^2 to about 600kg/cm^2. To calculate the flexual strength of the critical section of a R/C column subjected to axial force, bending moment and shear force, bending moment-compressive force interaction curve of concrete (Mc-Nc curve) is proposed in this paper. The Mc-Nc curve is much bigger than that obtained by using 0.85・σ_B stress value of stress block, which has been used for a long time to estimate the flexual strength of R/C section.