锈蚀钢材偏心受压钢柱承载性能退化规律

为研究腐蚀损伤对偏心受压钢柱承载性能的影响,首先对7根H型钢构件进行了最长达3 a的户外暴露盐雾加速腐蚀试验,并从各锈蚀钢构件端部截取板材试样进行力学性能试验,建立了各项力学性能参数与锈蚀率的关系式.然后分别对2根未锈蚀H型钢柱和7根锈蚀H型钢柱进行承载力试验,结果表明:随着锈蚀程度的不断加深,H型钢柱的承载力、刚度、位移延性系数呈逐渐下降趋势,对应失稳变形呈逐渐增大趋势;腐蚀损伤削弱了锈蚀钢柱的刚度和应变强化效应,影响了锈蚀钢柱的塑性性能,导致塑性发展系数随锈蚀率的增大而减小.最后,利用验证后的有限元模拟方法对不同截面尺寸和长度的压弯钢柱进行数值计算分析,建立了偏心受压钢柱的整体稳定承载力、塑性发展系数随锈蚀率的退化规律公式.

Deterioration law of bearing properties for corroded eccentric steel columns

This paper studied the effect of corrosion damage on bearing properties of eccentric steel columns. Outdoor exposure salt spray accelerated corrosion tests of 7 H-type steel members were performed for 3 years at most, and then the material tests, of which the specimens were extracted from end region of the members, were conducted to investigate the relationship between the corrosion rate and the mechanical properties. Through the experiments of 2 non-corroded H-type columns and 7 corroded H-type columns, the experimental results show that the bearing capacity, stiffness and ductility ratio decrease with increasing corrosion degree, and the corresponding deflection increases. The stiffness and strain hardening effect are weakened by corrosion damage, which influences the plastic property and decreases the plastic adaption coefficient. The corroded compression-bending column models with the various sectional dimensions and lengths were calculated by using the validated fem simulation method, hereby, the deterioration law formulas of the bucking strength and the plastic adaption coefficient were established based on the corrosion mass loss ratio.