局部损伤偏心受压钢构件FRP加固后的大挠度屈曲分析

Analysis of Large Deflection Buckling of Eccentric Compression Steel Members With Local Damage by FRP Strengthening

为了解决具有多区域局部损伤偏心受压钢构件FRP(纤维增强复合材料)加固后整体弯曲刚度的评价和大挠度屈曲分析计算缺乏实用方法的问题,考虑任意多区域局部损伤以及FRP对钢压杆整体弯曲刚度的贡献,采用能量方法推导损伤钢压杆FRP加固后的整体等效弯曲刚度.基于大挠度理论,研究局部损伤偏心受压钢构件FRP加固后的变形特性,推导了杆件屈曲后的杆端转角、挠度与荷载之间的函数表达式,并对影响抗屈曲性能的主要参数(如损伤位置、FRP厚度及偏心距等)进行参数分析.结果表明:损伤位置、FRP厚度及偏心距对钢压杆的抗屈曲性能影响明显,FRP抗屈曲加固方法可以显著提高局部损伤偏心受压钢构件的抗屈曲能力.

A method of analyzing of large deflection buckling behaviors and calculating integral bending rigidity of eccentric compression steel members with local damage strengthened with FRP lacks practical was proposed in this paper. Considering the contribution of multiple local damage and FRP, integral equivalent bending rigidity was deduced by using energy approach. Based on the large displacement theory,the large deflection buckling of eccentric compression steel members with local damage by FRP strengthening was studied. The post buckling angle, deflection, load function of eccentric compression steel members was deduced. The influencing rule of damage position, FRP thickness and eccentricity of stability of hollow pipe with local damage by FRP strengthening was obtained. The analysis shows that the effect of damage position, FRP thickness and eccentricity of anti-buckling capability of steel compression members is obvious. And the carbon fiber reinforced method can significantly improve the ability of anti-buckling.