关键词: 矩形钢管混凝土柱, 局部屈曲, 偏心荷载, 应力梯度系数, 伽辽金法, 临界屈曲应力

Abstract: The use of thin steel plates in rectangular concrete-filled steel stub columns will give rise to the local buckling that would reduce the strength，stiffness and ductility performance of the rectangular concrete-filled steel stub columns. The changes of local critical buckling stress (σcr) of the rectangular concrete-filled steel stub column under the eccentric loading are analyzed. Thus，the eccentricity is described by adopting the stress gradient coefficient φ and the formula for calculating the critical local buckling stress σcrof the rectangular concrete-filled steel stub columns is deduced by Galerkin method. From the formula，it is known that the local critical buckling stress (σcr) of steel plates of rectangular concrete-filled steel columns decreases with the increase of stress gradient coefficient φ. In addition，the axial force is disadvantageous to the local buckling of the rectangular concrete-filled steel stub columns.

Key words: rectangular concrete-filled steel columns, local buckling, eccentricity, stress gradient coefficients, Galerkin method, critical local buckling stress