摘要
该文提出了一个关于Z形檩条水平x轴受弯时求解畸变屈曲与弯扭屈曲的统一模型。这个模型不仅可以求解畸变屈曲,还能够同时求解整体弯扭屈曲。对比Hancock所提出的模型,该文所提的模型在考虑了腹板提供翼缘——卷边截面的一个转动弹簧和一个水平弹簧的基础上,还考虑了两个弹簧之间的相互作用。采用Ritz法给出了相应的解析解。并将20个常用Z形截面的计算结果与有限元结果进行了对比,结果吻合非常好。同样,也与Hancock方法的结果进行了对比。此外还与Timoshenko给出的整体弯扭屈曲的解析解进行了对比,说明了用该文方法求解整体屈曲的合理性。拟合了Z形截面畸变屈曲系数的公式,与有限元结果对比后有非常好的精度。
A unified model for the distortional and lateral buckling of cold-formed Z-purlins subjected to bending is proposed in this paper. The model can study both the distortional buckling and the global buckling. The new model is different from Hancock＇s model. Two interactive springs between lateral and rotational restraints were introduced in this model. They were provided by the web and rest of the purlin to the flange-lip section. The Ritz method was used to acquire a closed-form solution. The elastic buckling coefficients of 20 purlin sections predicted by the solution showed an excellent agreement with those from Finite Element Method （FEM）. Those results were also compared with the Hancock＇s method. The lateral bucking results given by the new model were compared with the Timoshenko critical moment as well, showing excellent agreement. The fitting formula for distortional buckling coefficients of Z-purlins was acquired, which was proved to have high-accuracy as compared to FEM results.
出处
《工程力学》
EI
CSCD
北大核心
2017年第5期116-124,131,共10页
Engineering Mechanics
基金
国家自然科学基金项目(51478421)
