本文介绍起重机桥架中的中轨箱型梁翼缘板在轮压力作用下考虑钢轨和翼缘板共同承载所引起的局部弯曲现象,根据板壳理论和力学知识,讨论导出了四边支承的翼缘板局部弯曲应力的计算方法和公式,其所依据的计算假定和原理比较简单,易于掌握,按这种方法计算中轨箱型梁较为符.合实际情况并能提高梁的承载能力. In this paper, the local bending phenomenon caused by the common bearing of rail and flange plates under the wheel pressure is introduced in the flange plate of the mid-rail box girder in the crane bridge. According to the theory and mechanical knowledge of the plate shell, The calculation method and formula of bending stress are based on the assumption and principle of calculation which is simple and easy to grasp. Calculating the mid-rail box girder according to this method is more suitable, which can improve the bearing capacity of the beam.