A study on flexural buckling strength Fcr of inelastic buckling for compressive members

Since Euler’s classical theory, which he proposed in 1759, many column curve formulations have been proposed. This study investigates the flexural buckling strength ( F cr ) calculated using the allowable stress design specification and the load and resistance factor design (LRFD) specification of the American Institute of Steel Construction. It is noted that the exponential function of the column curve formulation using LRFD is difficult to use in practice. Therefore, a simple parabolic function is proposed for the inelastic buckling strength of a steel column loaded with uniaxial compression, and it is shown to be consistent with many design codes. The expressions for inelastic buckling strength formulation as defined previously for ASD are used here. To verify the proposed equation, 118 individual test results of steel columns are examined. The mean of the ratio of the column strength to the proposed flexural buckling strength is 1.089, indicating that the proposed strength curves are in good agreement with the test results.