Abstract: Taking LNG tank containers as research objects, the strength reserve and displacement field of the tank were given by establishing its finite element model under stacking test conditions. The stacking buckling of the tank frame structure under multiple real loads was analyzed and calculated by using the Block Lanczos method, and the buckling modes of the frame and the corresponding critical loads were given. The strength distribution, the weakness, stability modes and macro stability reserves of the tank structure were clarified. It was concluded that the weak parts of the tank under stacking test conditions were upper frame short section and connection between frame and tank. The upper frame short section was the preferred location for stiffness reinforcement. In addition,the analysis shows that the stability of the tank frame is high and strength is the primary consideration in the design of this type of tank frame. This paper provided a reference for the design and check of the strength and stability of similar structures.

Key words: Stacking, Eigenvalue buckling, Strength, LNG, Finite element

摘要： 　以LNG罐式集装箱为研究对象，通过建立其在堆码试验工况下的有限元模型，给出罐箱的强度储备及位移场。采用Block Lanczos方法对多重实际载荷同时作用下罐箱框架结构堆码屈曲进行了分析和计算，给出了框架的屈曲模态及对应的临界载荷。明确了该罐箱结构的强度分布、薄弱环节、稳定性模态及宏观稳定性储备等；得出该罐箱在堆码试验工况下强度薄弱部位为外框架上短节和外框架与筒体连接部位，刚度补强的首选位置为外框架上短节部位。此外，分析表明该罐箱的框架具有较高的稳定性，强度问题是该类罐箱框架在设计环节中应首要考虑的问题，研究结果为类似结构的强度及稳定性设计校核提供了参考。

关键词: 堆码, 特征值屈曲, 强度, LNG, 有限元