钢—混凝土组合长柱极限承载力分析的数值方法

Ultimate strength analysis of slender steel reinforced concrete column by numerical method

对于复杂截面两端铰接的钢—混凝土组合长柱在双向偏压荷载作用下极限承载力分析,提出了一种新的数值迭代计算方法。考虑长柱在轴向荷载作用下的附加弯矩影响(二阶效应),先将长柱离散成若干等长的柱段,利用差分方法求得各柱段截面上的挠度与曲率的关系,再根据各截面上外力与抵抗力的平衡条件,得到一组关于荷载与变形关系的非线性代数方程组,最后,采用载荷增量法进行迭代求解。该数值方法的计算结果与试验结果吻合良好,验证了计算方法的正确性和有效性,可供工程设计参考。

A new numerical analysis method is presented for the ultimate strength analysis of two side pinned slender steel reinforced concrete column of arbitrary section subjected to biaxial eccentric compression . Considering the additional bending moments of the axial load about the lateral displacements （ i. e. the second-order effect）, the column is first divided into a finite number of small segments in equal length. The deflection-curvature relation of each segment is determined using the finite-difference method. The final nonlinear algebralcequations are then obtained by means of the equilibrium condition for each segment. The load increment method is used for the solution of the nonlinear algebraic equations finally. The analytical results agree well with those of tests, this demonstrates the validity and accuracy of the proposed method, this method can be referred in engineering design.