The previous energetic variational analysis of critical loads and of the choice of finite strain measure for structures very weak in shear, remaining in a state of small strain, is extended to the initial postcritical behavior. For this purpose, consideration of the transverse deformation is found to be essential. It is shown that imperfection sensitivity of such structures, particularly lamina...

We study the effect of a dimple-like geometric imperfection on the critical buckling load of spherical elastic shells under pressure loading. This investigation combines precision experiments, finite element modeling and numerical solutions of a reduced shell theory, all of which are found to be in excellent quantitative agreement. In the experiments, the geometry and magnitude of the defect ca...

A knock-down factor is commonly used to take into account the obvious decline of the buckling load in a cylindrical shell caused by the inevitable imperfections. In 1968, NASA guideline SP-8007 gave knock-down factors which rely on a lower-bound curve taken from experimental data. Recent research has indicated that the NASA knock-down factors are inclined to produce very conservative estimation...

Geometrical imperfection, which is generally a result of manufacturing process and service conditions, plays crucial role in load-bearing capacity shell structures. This study presents numerical on knockdown factors cylindrical shells as torsional Mode-I type geometric imperfections under compressive loads. The deformation patterns obtained from liner bifurcation analysis (LBA) for shape are us...

At the initial stage of design, structural strength and stability load-bearing members aircraft are mainly considered. In this paper, a support assembly analyzed. First, analysis, under design load 30.151 KN, numerical analysis shows that, in stress concentration area, peak value is 571.9 Mpa. The experimental strain sensor S6 position compared with results, error within 2.5%, which verifies va...

In this study, buckling analysis of panel types of marine and offshore structural components with initial imperfection under the combined action of lateral pressure and axial compression is carried out. The governing differential equations for thin and moderately thick shells are developed in terms of components of the displacement field. The governing ordinary differential equations are then d...