非线性金属结构材料轴压短柱承载力直接强度法

Direct strength method for predicting the carrying capacity of axiallyloaded stub columns of nonlinear metallic materials

为研究非线性金属结构材料轴压短柱承载力,汇总国内外关于不锈钢和铝合金轴压短柱的试验数据,建立相应有限元模型,对轴压短柱承载力进行数值分析,得到1 164个不锈钢和铝合金轴压短柱算例。对比分析了归一化屈服强度、应变硬化指数、局部几何初始缺陷和焊接残余应力4类关键参数对非线性金属结构材料轴压短柱承载力的影响。基于试验和有限元分析结果,提出了不同材料、不同截面形式轴压短柱对应的承载力直接强度法计算公式,以及统一形式的非线性金属结构材料轴压短柱承载力直接强度法计算建议公式,并对建议公式的准确性进行了验证。

In order to study the load-carrying capacity of axially loaded stub columns made of nonlinear metallic materials, the experimental data of stainless steel and aluminum alloy stub columns at home and abroad were summarized, and the corresponding finite element(FE) models were developed. Numerical analyses of the loadcarrying capacity of axially loaded stub columns were carried out, and a total of 1 164 stainless steel and aluminum alloy stub columns were studied. The influences of the four key parameters,the normalized nominal yield strength, the strain hardening exponent, the initial local geometric imperfection, and the residual stress,on the load-carrying capacity of axially loaded stub columns made of nonlinear metallic materials were compared and analyzed. Based on the experiments summarized and FE analyses results, the formulas of direct strength method for bearing capacity of different materials with different sections were put forward, and the unified formula of direct strength method for bearing capacity of axially loaded stub columns made of nonlinear metallic materials was suggested. Finally, the accuracy of the proposed formula was verified.