新型冷弯薄壁型钢屋架结构承载力分析

Analysis on Load-Carrying Capacity of New Cold-Formed Thin-Walled Steel Roof Truss

基于已完成的G550冷弯薄壁型钢屋架结构承载力试验,采用通用有限元软件ANSYS,建立考虑材料和几何非线性的分析模型.分析结构的特征值屈曲和非线性屈曲承载能力,通过对比试验数据结果,研究屋架结构的合理分析模式.结果表明,屋架结构的破坏模式为上弦杆的整体弯扭屈曲,与试验观测到的现象一致,极限承载力和试验结果非常接近.研究表明,有限元分析模型设计合理,节点处自由度耦合的手段能模拟自攻螺钉连接的受力情况.

Based on the experiments of G550 cold-formed thin-walled steel roof truss structures, an analysis model considering geometry and material non-linearity is established using general FEM software ANSYS. Both eigenvalue buckling and non-linear stability analysis of this structure are performed, a reasonable analysis model for roof truss structure is studied by comparing with test data. The results showed that the failure mode of roof truss is flexual-torsional buckling of top chord members, which accords with the phenomena observed during test, the ultimate load-bearing capacity is also very close to test data. The study demonstrates that the FEM analysis model is rational , the measure of coupling nodes＇ degree of freedom can simulate force state of self-taping screw connections.