Stochastic amorphous Pd43Ni10Cu27P20 foams were tested in quasistatic and dynamic loading. The strength/porosity relations show distinct slopes for the two loading conditions, suggesting a strain-rate-induced change in the foam yielding mechanism. The strength/porosity correlation of the dynamic test data along with microscopy assessments support that dynamic foam yielding is dominated by plast...

APPROACH: Buckling driven delamination is difficult to control in experiments. Thus, the present study relies on numerical simulations using geometrically nonlinear finite element analysis as well as the softening foundation model, which is an adaptation of Winkler elastic foundation. Delamination fracture is modeled by a cohesive crack model. Dimensionless variables are used to cover the entir...

The objective of this paper is to quantify how nanoscale surface stresses impact the critical buckling strains of silicon nanowires. These insights are gained by using nonlinear finite element calculations based upon a multiscale, finite deformation constitutive model that incorporates nanoscale surface stress and surface elastic effects to study the buckling behavior of silicon nanowires that ...

The elastic buckling modes of pultruded I-beams subjected to various loading conditions are studied. The coupling of lateral and distortional buckling, very likely to appear in thin-walled cross-sections, is investigated. Plate theory is used to allow for distortion of the cross-section. Shear effects and bendingt\\isting coupling are accounted for in the analysis, because of their significant ...

Composite steel shear wall is a lateral load resisting system which consists of a steel plate with concrete wall attached to one or both sides to prevent it from elastic buckling. The composite behavior is ensured by utilizing high-strength bolts. This paper investigates the effect of distance between bolts, and for this purpose 14 one-story one-bay specimens with various bolts spacing were mod...

The earliest example of bifurcation is the buckling of of an elastic beam. In engineering, buckling is a failure mode characterized by a sudden failure of a structure subjected to high compressive stresses, where the actual compressive stresses at failure are greater than the ultimate compressive stresses that the material is capable of withstanding. This mode of failure is also described as fa...

Pattern transformation in periodic microporous elastoplastic solid coatings is caused by a buckling of the struts and a rotation of the nodes under compressive stresses. The results of a nonlinear numerical investigation confirm the critical role of the bifurcation of the periodic solid under compressive stresses. In striking contrast to the earlier observations of elastic instabilities in poro...

We introduce a novel concept for the design of programmable-elasticity metamaterials; materials whose elastic properties can be modified instantaneously and reversibly on demand. Real-time tunable linear and nonlinear elastic moduli are obtained in lattice materials by adjustment of strut connectivity via actuation of embedded electromagnetic locks. The Young’s modulus and Poisson’s ratio of pr...

Buckling of cylindrical sandwich shells subject to axial compression is addressed for shells having foamed metal cores. Optimal face sheet thickness, core thickness and core density are obtained which minimize the weight of a geometrically perfect shell with a speci®ed load carrying capacity. Constraints imposed by wrinkling and yielding of the face sheets and yielding of the core are all consi...

This paper is devoted to the buckling analysis of thin composite plates under straight single-walled carbon nanotubes reinforcement with uniform distribution and random orientations. In order to develop the fundamental equations, the B3-Spline finite strip method along with the classical plate theory (CPT) is employed and the total potential energy is minimized which leads to an eigenvalue prob...