工形对称不锈钢梁变形性能的有限元分析

Finite Element Analysis of the Deformation Behavior of Stainless Steel I-beams

为了研究国产不锈钢梁的变形性能以及残余应力模型和不锈钢材性对其的影响,采用了多种计算方法得到不锈钢梁的荷载—挠度曲线,并通过试验进行验证。这些方法分别为:通用有限元软件ANSYS数值模拟,本课题组王元清教授推荐的修正方法,E Real等人提出的简化方法以及欧洲规范3推荐的计算方法。采用的残余应力模型分别为Gardner和本课题组推荐的残余应力模型。不锈钢材性分别取自不锈钢母材、焊接后梁截面以及欧洲规范3推荐的数值。结果表明:在有限元分析中,残余应力模型对不锈钢梁荷载—挠度的影响不明显,材性对其影响主要体现在极限承载力上,采用母材或焊接后材性数据得到的荷载—挠度曲线相差不大,均可在有限元分析中采用;在理论计算中,采用焊接后材性数据计算结果最接近试验值;各方法得到的挠度均小于试验值。本文的分析结果可为不锈钢梁的挠度计算提供依据。

To study the deformation behavior of domestic stainless steel I-beams and the influence of residual stress model and mechanical properties of the material, several methods were used to obtain the load-deflection curves of the stainless steel I-beams, and the results were also compared with the experiment. The methods include the finite element analysis, the simplified methods proposed by Prof. Wang, Prof. E Real and EN 1993-1-4 Eurocode 3 respectively. The residual stress models used were proposed by Prof. Gardner and Prof. Wang. The stress-stain curves of the material are got by specimens extracted from the base material and the fabricated section, as well as by the values of EN 1993-1-4 Eurocode 3 The results show that in the finite element analysis the effect of residual stress model on the load-deflection curve is not apparent, the effect of mechanical properties is reflected mainly on the ultimate bearing capacity, the difference between load-deflection curves obtained by mechanical properties of base material and fabricated section is little and both could be used in the finite element analysis. When calculated with simplified methods, the load-deflection curve obtained by mechanical properties of fabricated section is the most accurate one; the deflections got by the above methods are underestimated. The obtained results can provide basis for the deflection calculation of the stainless steel beams.