Buckling Analysis of Reticulated Shells

Abstract

The paper presents a comparatively simple method for assessing the global stability of single- and double-layer reticulated shells, assuming rigid connections between the bars. With knowledge of the rigidities of the reticulated shell, a statically equivalent replacement solid shell is established, the buckling of which is extensively treated in the literature. The critical load of this replacement continuum is determined by taking into account the influences of geometric imperfections (eccentricity), plasticity, (local) bar buckling and – in the case of double-layer reticulated shells – of transverse shear deformation. All these are presented in detail for isotropic shells, but the method can also be used for anisotropic ones. Finally, for dimensioning reticulated shells, a unique safety factor based on the theory of probabilities is recommended, which depends on the uncertainties of the various effects. Numerical values for the safety factor are also given. The method proposed provides a transition from shells to plane plates, from surface to bar structures, and from reticulated to solid shells, thus ensuring identical safety levels for all these structures.

Analysis based evaluation for buckling loads of two-way elliptic paraboloidal single layer lattice domes

“…8 for the dome whose members were proportioned using γ = 0.2 under a uniform vertical load. Here γ is a factor used in the member proportioning [5] to avoid too small members within a Several values for F S B and F S M were given in this study as shown in Table 4, and one of them is a set of values proposed by Kollar and Dulacska [12]. If a set of appropriate safety factors are selected considering possible effects, for examples, due to load conditions, geometric imperfections, construction process and other factors, the allowable axial force is evaluated using (12) depending on compression and tension.…”

“…(15) can be applied for estimating the buckling load factor if we use an appropriate strength interaction for design, since proper margins are provided using Eqs. (11) and (12). If one traces back to the procedure for estimating the buckling load factor, Eqs.…”

Buckling Load of Elliptic Paraboloidal Single Layer Reticulated Roofs with Simple Supports under Uniform Load

“…8. One is a curve of AIJ for allowable stress design [19] and the other one is a modified Dunckerly equation [4,20] as follows: (22) If the curve of modified Dunkerley equation, Eq. (22), with γ 0 = 1.0 is applied, the elastic-plastic column buckling for the specific member (m) can be evaluated with a safer margin.…”

“…However, it considers reinforced concrete shells as its target. For steel spatial structures, based on the probability theory, Dulacska and Kollar [22] presented 1.75 for plastic failure and 2.50 for elastic buckling. In this report, we adopt the two distinct safety factors as F SM = 1.75 for plastic failure and F SB = 2.50 for elastic buckling.…”

Analytical Prediction of Steel Grid-Shell Stability and Dynamic Behaviors Using Neural Networks – Part 1

“…The state of the art regarding the stability of grid-shells was thoroughly expounded by Gioncu (1994). Most of the available analytical solutions predicting buckling of reticulated shells resort to the homogenization technique, treating the structure as a continuum shell (Dulácska and Kollár 2000, Kato 2005, Lefevre 2015. The analytical solution presented in this paper doesn't rely on this simplification.…”