Buckling Analysis Problems
This chapter contains a buckling analysis problem and Structure's results. In a buckling analysis, Structure calculates buckling load factors and mode shapes that determine the critical magnitudes of load at which a 3D structure will buckle. Structure also automatically calculates all predefined measures. This list of measures differs based on the analysis type.
This chapter contains the following models:
mvsb002: Buckling Analysis of Composite Lay-up
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Analysis Type:
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Buckling Transversely Isotropic
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Model Type:
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3D
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Comparison:
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MSC/NASTRAN
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Reference:
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Jones, R.M., Mechanics of Composite Material, Hemisphere Publishing Corp., 1975, pp 260-261.
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Description:
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A four-layered transversely isotropic square plate is simply-supported and subjected to an in-plane load. Determine the buckling load factor.
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Specifications
Element Type: | shell | ||
Units: | IPS | ||
Dimensions: | length: 10 width: 10 thickness: 0.1 | ||
Ply lay-up: 0/90/90/0 | Thickness of each ply: 0.025 | ||
Shell Properties: | |||
Extensional Stiffness | A11=1.54e06 | A12=18,779 | A16=0 |
A16=0 | A26=0 | ||
A66=37,500 | |||
Extensional–Bending Coupling Stiffness | B11=0 | B12=0 | B16=0 |
B22=0 | B26=0 | ||
B66=0 | |||
Bending Stiffness | D11=2,198.75 | D12=15.6495 | D16=0 |
D22=367.762 | D26=0 | ||
D66=31.25 | |||
Transverse Shear Stiffnesses | A55=32,553 | A45=0 | A44=17,940 |
Material Properties: | |||
Mass Density: 0.002 | Cost Per Unit Mass: 0 | ||
Young's Moduli | E1=3e7 | E2=750,000 | E3=750,000 |
Poisson's Ratio | Nu21=0.25 | Nu31=0.25 | Nu32=0 |
Shear Moduli | G21=375,000 | G31=375,000 | G32=E2/[2*(1+Nu32)] |
Coefficients of Thermal Expansion | a1=0 | a2=0 | a3=0 |
Constraints: | Fixed in out of plane (z-direction) translation along all outer edges (AB, BC, CD, and DA). Fixed in translation in all directions at point D Fixed in x & z-direction translation at point A | ||
Loads: | In-plane force/unit length load=1: in +x-direction along edge DA in -x-direction along edge BC | ||
Comparison of Results Data
Theory | Structure | % Difference | |
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Buckling Load Factor | 268.73 | 267 | 0.6% |
Convergence %: 0.0 % on buckling load factor. | Max P: 6 | No. Equations: 455 | |