加筋壁板轴压载荷下后屈曲稳定性试验研究

Post-buckling and Stability Studies of Curved Stiffened Panels Subjected to an Axial Compression Load

对11种构型的民用飞机机身加筋曲板在轴压载荷下后屈曲承载能力进行了试验和工程算法研究,深入探索了机身壁板的各种破坏模式,对极限法、Johnson)物线法与欧拉法三种工程算法比较,并且把试验结果与计算结果进行了对比。研究结果表明:壁板后屈曲轴压许用值与桁条剖面积和蒙皮厚度成线形关系,主要取决于桁条剖面积;蒙皮的局部屈曲应力对初始缺陷敏感,但局部屈曲应力的偏差对壁板的轴压破坏载荷影响不明显;与工程计算结果对比发现Johnson抛物线法计算的破坏轴压与试验结果吻合较好。

Results obtained from experiments and approximate computations for 11 stiffened curved aluminum panels which are used for large-scale civil aviation plane airframe and subjected to an axial compression load, have been presented in this paper. Various damage modes of these panels were detailed explored. Three approximate computational methods including Limit Method, Johnson＇ s Parabola Method and Euler-Engesser Method were applied for these panels. After comparing between the approximate computational and the experimental results, it reveals that the maximum post- buckling load is sensitively affected by the skin thickness, and especially by the cross-section area of stringers. In addition, the buckling stress is found to be influenced by the initial defection, whereas, the damage load of the considered structures is not sensitive to it. Comparing with experimental results, it is found that the Johnson＇s Parabola Method is more suitable for the discussed problem and leads .more reasonable results.