Steel corrugated shear wall (SCSW) is an alternative to traditional shear walls with flat plates. However, shear resistance behavior and design of the infilled corrugated panels in SCSWs has not been ...well studies. This paper focuses on the shear resistance of sinusoidally corrugated panels in SCSWs under monotonic lateral shear force, via finite element analyses (FEA) considering both geometric nonlinearity and material elasto-plasticity. Firstly the effects of initial imperfections and geometric dimensions on shear resistance of corrugated panels are explored. Then based on extensive FEA, the maximum and the post-buckling strengths are investigated, and fitting equations to predict the shear resistant behavior of corrugated panels are proposed by introducing the normalized height-to-thickness ratio. It is found that, the maximum shear resistance of corrugated panels has a consistent relationship to the normalized height-to-thickness ratio, however variation of the post-buckling resistance is complex and geometric parameters have to be properly chosen to avoid significant strength drop after buckling. The equations proposed agree with the FEA results, and can be utilized in design of corrugated panels in SCSWs.
•Corrugated panels under shear are sensitive to geometric imperfections.•Equations for the maximum shear resistance for corrugated panels are proposed.•Equations for residual resistances are for good post-buckling behavior.•Load-displacement curves of corrugated panels under shear can be predicted.
Finite element asymptotic post-buckling analysis, being based on fourth-order expansions of the strain energy, requires that nonlinear structural modeling be accurate to same order, at least with ...respect to the rigid motions of the elements. A corotational description is proposed here as a general tool to satisfy this requirement of objectivity, by referring each element to a local frame which moves (rotates) with the element, so filtering its rigid motion. In this description nonlinearity of the problem derives essentially from the change of reference, from the global fixed frame to the local one, the strain energy being governed by their relative rotations. In finite kinematics, this noticeably complicates the algebra for obtaining exact expressions of its variations.
Quite simple, basic expressions for the first four corotational derivatives of the strain energy are provided, allowing the set up of a fourth-order accurate asymptotic analysis starting from standard finite elements based on linear or simplified nonlinear local modelings. The formulation is implemented for the analysis of 3D beam assemblages and several numerical results are presented and discussed showing the effectiveness and robustness of the proposed approach in reproducing the nonlinear equilibrium path in both cases of monomodal and coupled multimodal buckling.
This paper presents and discusses numerical results, obtained through Ansys shell finite element analyses, dealing with the post-buckling behaviour (mostly elastic, but also elastic–plastic), ...ultimate strength and failure mode nature of fixed-ended and pin-ended thin-walled equal-leg angle steel columns with coincident critical flexural-torsional and minor-axis flexural buckling loads (i.e., experiencing very strong coupling effects between these two global instability phenomena) – for comparative purposes, columns that are buckling in pure flexural-torsional and flexural modes are also analysed. Since the main aim of the work is to investigate the column imperfection-sensitivity, the analyses concern otherwise identical columns containing initial geometrical imperfections with different shapes and amplitudes, combining the competing critical buckling modes – particular attention is paid to the sign of the minor-axis flexural component. The results reported consist of column (i) elastic equilibrium paths and the corresponding peak loads and deformed configurations and (ii) elastic–plastic collapse loads and mechanisms, making it possible to assess how they are influenced by the initial geometrical imperfections.
•Mode interaction effects in thin-walled equal-leg angle columns with intermediate lengths.•Interaction between major-axis flexural-torsional and minor-axis flexural buckling modes.•Determination of the less and most detrimental critical-mode initial imperfection shapes.•Imperfection-sensitivity analyses of the column post-buckling behaviour and ultimate strength.•Maximum elastic and elastic–plastic column failure load erosion due to interaction effects.
Spacecraft devices have strict restrictions on weight and volume for high fuel efficiency and endurance requirements. In this paper, a method for designing an ultrathin passive vibration isolator ...based on multi-layer plain-woven wire mesh is proposed. The isolator is structurally inspired by O-type wire rope isolators, and the wire mesh is pre-compressed to buckling for lower stiffness and higher stability. The isolator stiffness in the post-buckling process is analyzed by simplifying the single wire as a strut. The motion equation of the strut is constructed and calculated by the fourth-order Runge–Kutta method and the shooting method. The morphology and stiffness variation of the wire mesh during pre-compression process and repeated compression process are analyzed, and the structural compaction ratio is calculated. This computational method has been experimentally validated and proven to be effective. To prevent collisions between the protected objects and the base during the shock process, the system is simplified and described using a single-degree-of-freedom (SDOF) system with displacement restrictors. The system’s motion equation is formulated and solved using the central difference method. Subsequently, the maximum compression displacement of the isolator is determined through the calculation. A wire mesh isolator with a thickness of less than 10 mm is fabricated for a specific application. Experimental results confirm that the isolation efficiency surpasses 65%, and the isolator is capable of withstanding a peak acceleration of 60 g while maintaining a shock acceleration magnification below 1.2.
•A method for designing vibration isolators composed of the wire mesh is proposed.•The isolator stability performance is enforced by pre-compressing the wire mesh.•The morphology and stiffness variation of the wire mesh are calculated.•The shock displacement amplitude is calculated using the central difference method.
Lattice structures have been used in a variety of engineering applications in aerospace, automobile and biomedical applications. In this study, the buckling analysis of additively manufactured ...cellular columns was conducted. The effect of unit cell size and height of the column on the critical buckling load and post-bucking behavior of compressive columns constructed with periodic cubic structure was investigated using experimental and simulation-based studies. The results exhibited that the unit cell size and cellular column height significantly affect the critical buckling load while the total mass, volume fraction, and column dimensions remain the same. The critical buckling load increases with the increase of unit cell size or decrease of cellular column height. The largest unit cell size (8.72 mm) has the maximum critical buckling load, followed by unit cell sizes of 4.74 mm and 2.5 mm, respectively. Moreover, the failure of cellular columns having larger height-to-width (h/w) ratio, happens due to global buckling, whereas, local bucking dominates for smaller h/w ratios. Additionally, it was found that the unit cell size significantly affects on the post-buckling behavior; the samples of larger unit cells failed in a brittle manner and this trend continuously changed from brittle to ductile as the unit cell size reduces.
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•The buckling and post-buckling of cellular columns having different unit cell sizes and column heights are studied.•Both unit cell size and cellular column height significantly affect the buckling and post-buckling.•The failure of cellular column occurs due to global and/or local buckling.•Brittle and ductile failure occurs in samples of larger and comparatively smaller unit cells respectivley.
•Compressive buckling behavior of damaged composite stiffened panel is investigated.•Skin between two ribs is the first location where the buckling failure occurs.•Stiffened panel still with a strong ...load capacity at post-buckling stage is verified.•Good agreement among theory, simulation and experiment has been achieved.•Advice for improving structural anti-buckling and material utilization rate is given.
The compressive buckling and post-buckling behaviors of J-type composite stiffened panels before and after impact load were investigated through theoretical, numerical and experimental methods. In this paper, the load-bearing characteristics, including the buckling strength, ultimate strength and failure process of the intact composite stiffened panels were theoretically predicted and tested. Next, the impact tests were carried out on both the center of the skin and the back of the rib of the J-type composite stiffened panel, and then the compression test was performed on the damaged stiffened panel. The residual strength and failure process of the damaged J-type stiffened panel were obtained. By means of numerical simulation, the effects of different degrees of impact damage at the center of the skin on the buckling and post-buckling behavior of stiffened panels were revealed. Good agreement among theoretical, numerical and experimental results has been achieved. Finally, the influence of the adhesive layer, lay-up method of both the stiffened rib and skins, and geometric dimensions of the J-type ribs on structural buckling and post-buckling behaviors was systematically studied. The outcome from this research provides reasonable suggestions for improving the buckling load, ultimate load and material utilization rate of stiffened panels.
This paper studies the spontaneous buckling morphology transition of an elastic ring confined in an annular region constraint. With the increase of uniform axial strain, the ring initially forms a ...symmetrical blister, and then the blister is compressed, spontaneously inclines and transits to the “S” shape. A theoretical framework based on the minimum potential energy theory is proposed to obtain the critical strain of morphology transition, which matches well with experimental results. The map predicting stable buckling shapes of the ring with different geometrical parameters is demonstrated, which may offer helpful guidance to practical applications, for example, the design of gear-less pump and rotary actuators.
•The complete spontaneous buckling transition of an elastic ring packed in an annular region constraint was investigated.•A theoretical framework was proposed to obtain the critical strain of morphology transition.•A map predicting stable buckling shapes of the ring with different geometrical parameters was demonstrated.•The proposed theory matched well with experiment.
As structures become slender their non-linear aspects become more apparent and needing of assessment. In that spirit, the authors proposed a theory for addressing the effects of these non-linearities ...in a highly flexible beam akin to an wing in aeroservoelastic analyses regarding piezoelectric control for flutter suppression. This framework was proven quite efficient for it allowed large displacements to be naturally incorporated by means of a set of generalized variables that encoded the beam mechanics (membrane and bending) and in which space some mechanical features could be linearized. Therefore, the authors investigated the consequences of solving analytically a cantilever beam problem subjected to a material load at its free tip by means of that theory and demonstrated the connection between that problem (in particular when it comes to the buckling problem) and the Weierstrass elliptic ℘-function, a relationship not yet demonstrated to the best of the authors’ knowledge. That demonstration is the subject of this article, as well as a comprehensive study of the solutions for some loading conditions in a reference slender beam and the suggestion of further applications that could be developed from the solution found, in particular in FE analysis.
•A new methodology for solving beam-like nonlinear problems is derived.•Analyses are performed with a set of dimensionless variables simplifying the problem.•A novel solution is obtained in terms of the Weierstrass elliptic ℘-function.•Formulation can be extended and combined with efficient numerical methods of solution.
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