Buckling-Restrained Braced Frame system(BRBFs) are a new type of steel seismic-load-resisting system that has found use in several countries because of its efficiency and its promise of seismic performance far superior to that of conventional braced frames. The system is addressed in the 2005 edition of the AISC Seismic Provisions for Structural Steel Buildings, also a set of design provisions ...

This paper describes an optimization procedure to design thermoplastic composite panels under axial compressive load conditions. Minimum weight is the goal. The panel design is subject to buckling constraints. The presence of the bending-twisting coupling and of particular boundary conditions does not allow an analytical solution for the critical buckling load. Surrogate models are used to appr...

the finite element method is employed for the flexural-torsional linear buckling analysis of beams of arbitrarily shaped composite cross-section taking into account generalized warping (shear lag effects due to both flexure and torsion). the contacting materials, that constitute the composite cross section, may include a finite number of holes. a compressive axial load is applied to the beam. the...

In this paper, individual and combined effects of distributed and local geometrical imperfections on the limit load of an isotropic, thin-walled cylindrical shell under axial compression are investigated. First eigen affine mode shape imperfection pattern (FEAMSIP) is taken as distributed geometrical imperfections and dent as local geometrical imperfections. Limit load of the cylindrical shells...

This paper investigates symmetrical buckling of orthotropic circular and annular plates of continuous variable thickness. Uniform compression loading is applied at the plate outer boundary. Thickness varies linearly along radial direction. Inner edge is free, while outer edge has different boundary conditions: clamped, simply and elastically restraint against rotation. The optimized Ritz method...

This paper is concerned with the inelastic behavior of axially loaded concrete-filled thin-walled steel tubular columns subjected to local buckling. A nonlinear fiber element analysis program accounting for local buckling effects is developed for predicting the ultimate strength and ductility of concrete-filled thin-walled steel tubular columns. The effects of local buckling are taken into cons...

iii Summary Computations were performed to determine the eect of an overall bow-type initial imperfection on the reliability of structural panels under combined compression and shear loadings. A panel's reliability is the probability that it will perform its intended function|in this case, carry a given load without buckling or exceeding in-plane strain allowables. For a panel loaded in compres...

The interaction between Euler buckling and Brazier instability in an orthotropic cylindrical tube was investigated. A simple closed-form interaction curve was obtained by using the principle of minimum potential energy including the 3D extended Brazier’s 2D type cross-section ovalization and the potential energy of axial compression. The interaction curve consists of an Euler buckling load and ...

Buckling of a simply supported three-layer circular cylindrical shell under axial compressive load is studied. The inner and outer layers of the shell are comprised of the same homogeneous and isotropic material, and the middle layer is made of an isotropic functionally graded (FG) material whose Young’s modulus varies either affinely or parabolically in the thickness direction from its value f...

Molecular dynamics (MD) simulations under transverse shear, uniaxial compression, and pullout loading configurations are reported for multiwall carbon nanotubes (MWCNTs) with different fraction of interwall sp3 bonds. The interwall shear coupling in MWCNTs is shown to have a strong influence on load transfer and compressive load carrying capacity. A new continuum shear-coupled-shell model is de...