Failure in cold-formed steel beams is generally initiated by one of three instabilities: local, distortional, or lateral-torsional buckling. For cold-formed steel joists, purlins, or girts, when the compression flange is not restrained by attachment to sheathing or paneling, distortional buckling may be the predominant failure mode. Experimental results on cold-formed steel beams with unrestrai...

Linear eigenvalue analysis of cracked cylindrical shells under combined internal pressure and axial compression is carried out to study the effect of crack type, size and orientation on the buckling behavior of cylindrical thin shells. Two types of crack are considered; through crack and thumbnail crack. Our calculations indicate that depending on the crack type, length, orientation and the int...

We report the results of a numerical and theoretical study of buckling in elastic columns containing a line of holes. Buckling is a common failure mode of elastic columns under compression, found over scales ranging from metres in buildings and aircraft to tens of nanometers in DNA. This failure usually occurs through lateral buckling, described for slender columns by Euler's theory. When the c...

Buckling of single-walled and multiwalled carbon nanotubes SWNTs and MWNTs, respectively due to axial compressive loads has been studied by molecular mechanics simulations, and results compared with those from the analysis of equivalent continuum structures using Euler buckling theory and the finite element method. It is found that a MWNT of large aspect ratio length/diameter buckles as a colum...

Arteries can buckle axially under applied critical buckling pressure due to a mechanical instability. Buckling can cause arterial tortuosity leading to flow irregularities and stroke. Genetic mutations in elastic fiber proteins are associated with arterial tortuosity in humans and mice, and may be the result of alterations in critical buckling pressure. Hence, the objective of this study is to ...

The nanomechanical properties of micropatterned nanomembranes containing gold nanoparticle microarrays were investigated with the buckling instability method. An unusual, complex pattern of buckling instability was observed for the nanoscale polymeric films under compressive stresses. An intriguing two-stage wrinkling was observed for these nanoscale films with spatially correlated instabilitie...

Individual multiwalled carbon nanotubes with a range of aspect ratios are subjected to cyclic axial compression to large strains using atomic force microscopy. Distinct elastic buckling and post-buckling phenomena are observed reproducibly and are ascribed to Euler, asymmetric shell buckling (i.e., kinking), and symmetric shell buckling. These show agreement with continuum theories that range f...

The paper focuses on the mechanics of a compliant serial manipulator composed new type dual-triangle elastic segments. Both analytical and numerical methods were used to find stable unstable equilibrium configurations, as well predict corresponding shapes. stiffness analysis was carried for both loaded unloaded modes, matrices computed using Virtual Joint Method (VJM). results demonstrate that ...