通过有限元方法分析了大型反应器钢结构体系的受力与变形的薄弱位置,并对反应器中大量使用的加劲薄钢板的屈曲性能进行了研究.在此基础上,实验分析了加劲板的稳定性.结果表明:矩形薄钢板开孔周围加加劲肋时,加劲肋对板起到嵌固作用;对于此反应器整体结构来说,薄板选择L形加劲肋最优;对于带有加劲肋的薄板,边界约束条件越强,临界屈曲荷载越大,板越不易发生屈曲.实验和数值结果有较好的一致性. The finite element method is used to analyze the weak position of the stress and deformation of the steel structure of large reactor and to study the buckling behavior of the stiffened steel plate used in large quantities in the reactor.On this basis, The results show that the stiffener plays the role of embedding on the plate when the stiffener is added around the opening of the rectangular thin steel plate. For the overall structure of the reactor, the L plate stiffener is the most suitable for the plate, , The stronger the boundary constraints are, the larger the critical buckling load is, the less prone to buckling is. The experimental and numerical results are in good agreement.