The results of unique experimental studies of buckling of dented axially compressed unstiffened cylindrical shells are provided in the suggested paper. The dimple-like geometrical imperfections of different shape, size, deflection amplitude, and number of dents were created on cylindrical shells before axial loading. The initial deflection amplitude varied in the wide range, up to several shell thicknesses. In all cases the plateaus were discovered on the buckling load initial deflection diagrams. Corresponding axial loads were close to local lower buckling loads of perfect shells. These loads are defined as minimum values of axial force when the post-buckling equilibrium states of the perfect structure with one or several dimples exist. It was shown that the lower local buckling loads slightly depend on geometrical imperfections and therefore can be used for estimation of design buckling load of the structure. Over 50 specimens were tested. Pre-buckling and post-buckling behavior of imperfect shells was studied.

在建议的论文中提供了凹形轴向压缩的未加硬圆柱壳屈曲屈曲的独特实验研究的结果。在轴向加载之前，在圆柱壳上产生了不同形状，大小，挠曲幅度和凹痕数量的凹坑状几何缺陷。初始偏转幅度在很宽的范围内变化，直至几个壳厚度。在所有情况下，都在屈曲载荷初始挠度图上发现了平台。相应的轴向载荷接近于理想壳体的局部较低的屈曲载荷。当存在带有一个或多个凹坑的理想结构的屈曲后平衡状态存在时，这些载荷定义为轴向力的最小值。结果表明，较低的局部屈曲载荷略微取决于几何缺陷，因此可用于估算结构的设计屈曲载荷。测试了50多个样本。研究了不完善壳的屈曲前和屈曲后的行为。