Eurocode (EC3) bending moment design model of mono-symmetric corrugated web girders (CWGs) is based on the critical failure mode among the tension flange yielding, the compression flange yielding and the lateral-torsional buckling (LTB) of the compression flange. Recently, LTB behaviour of S460 laterally-unrestrained mono-symmetric CWGs with fully-effective flanges has been investigated by the authors, from which EC3 design model has been modified to better represent their actual strength. Nevertheless, the effect of the local buckling (LB) of slender compression flanges on the flexural strength and behaviour of such long girders has not been examined. While the corrugated web potentially makes large contribution to the out-of-plane stiffness, LB of the compression flange is expected to reduce LTB resistance of such girder significantly. Principally, this paper is devoted to exploring such effect on the accuracy of EC3 bending moment design model. Currently, virtual tests, by using ABAQUS software, are generated based on accurate validation. Then, parametric studies, intentionally designed to eliminate the tension flange yielding, are carried out on simply supported girders considering mainly the influences of the flange and web dimensions on the behaviour of S460 mono-symmetric CWGs. The strengths of such girders are compared with EC3 design model, from which it is found to provide unsuitable predictions. Hence, new formula has been proposed to accord better with the FE results. Additionally, several conclusions are provided at the end to assist design engineers in suggesting efficient cross-sections.

单对称波纹腹板梁（CWG）的Eurocode（EC3）弯矩设计模型基于拉伸凸缘屈服，压缩凸缘屈服和压缩凸缘的横向扭转屈曲（LTB）中的临界破坏模式。最近，作者研究了具有完全有效法兰的S460横向无约束单对称CWG的LTB行为，并从中修改了EC3设计模型以更好地体现其实际强度。尽管如此，细长压缩法兰的局部屈曲（LB）对如此长的弯曲强度和行为的影响大梁尚未检查。尽管瓦楞纸幅可能会对面外刚度做出很大贡献，但压缩法兰的LB有望显着降低这种梁的LTB抵抗力。主要地，本文致力于探索这样的影响对EC3弯矩设计模型的准确性。当前，基于ABAQUS软件的虚拟测试是基于准确的验证生成的。然后，在主要考虑到法兰和腹板尺寸对S460单对称CWG的性能的影响的情况下，对简单支撑的梁进行了有意设计来消除张拉法兰屈服的参数研究。将此类大梁的强度与EC3设计模型进行比较，发现该模型无法提供适当的预测。因此，已经提出了新的公式以更好地与有限元结果相吻合。此外，最后提供了一些结论，以帮助设计工程师建议有效的横截面。