中文摘要：

考虑任意多区域局部损伤和FRP材料对变截面钢压杆弯曲刚度的贡献以及初弯曲、初偏心两种几何缺陷的耦合影响,首次基于大挠度理论建立了FRP加固变截面损伤钢压杆的稳定微分方程。提出一种将杆轴初始挠度近似拟合成圆弧的初弯曲模型,推导出压杆大挠度屈曲时最大挠度、荷载与杆端转角之间的函数关系。建立了基于边缘屈服准则的弯矩作用平面内稳定承载力的计算公式。探讨了局部损伤、FRP粘贴厚度、初弯曲、初偏心等参数对变截面局部损伤钢压杆FRP加固后的大挠度屈曲性能的影响。数值算例与已有文献对比和参数分析证明了本文解析算法、公式及结论的正确性和有效性。

英文摘要：

Based on the large displacement theory, the stability differential equations of non-uniform steel members with local damage by FRP strengthening are firstly derived, in which the contribution of multiple local damage, FRP materials, initial bending and initial eccentricity are considered. A new circular-arc model is proposed for describing initial bending of member. Functional relations are deduced between the post buckling deflection, load function and angle of steel member. The formulas of calculating in-plane stability capacity are deduced in terms of outmost fiber yielded criteria. The main factors such as local damage, FRP thickness, initial bending and initial eccentricity affecting on anti-buckling capability of steel compression members are discussed. And the numerical results are compared with those from the existed documents, which shows that the suggested method, formulas and conclusions are correct and efficient.