8.2 KiB
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Int 4x2x2
(a)
Model I - distorted
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(b)
Model III - distorted
Figure 12: Large deflection analysis of a cantilever using distorted elements
Table 8 Results for large deflection analysis of a cantilever using distorted elements
| Model I (distorted) | Model III (distorted) | |||||
| step 2 | step 5 | step 8 | step 2 | step 5 | step 8 | |
| $\phi^{FEM}/\phi^{analyt}$ | 0.13 | 0.13 | 0.13 | 0.95 | 0.84 | 0.76 |
| $u^{FEM}/u^{analyt.}$ | 0.01 | 0.01 | 0.01 | 0.89 | 0.68 | 0.56 |
| $w^{FEM}/w^{analyt}$ | 0.10 | 0.11 | 0.12 | 0.95 | 0.86 | 0.81 |
| $\phi^{analyt}$ | 18° | 45° | 72° | 18° | 45° | 72° |
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P 2a h 2a R1 R2
(a) Spherical shell
line
| Central deflection, Wc | Central load, (P/1000) |
|---|---|
| 0 | 0 |
| 50 | 30 |
| 100 | 45 |
| 150 | 50 |
| 200 | 40 |
| 250 | 35 |
| 300 | 55 |
(b) Non-linear load displacement curve.
Figure 13 Geometric non-linear response of a spherical shell. O, Horrigmoe; —, Leicester; ●, nine 4-node elements; □, one 16-node element Int 4×4×2
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ε ε 102. 54. 0.54 0.5 4
(a) Stiffened plate
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| Vertical displac. of center | τ/τ_CR |
|---|---|
| 0.004 | 0.95 |
| 0.008 | 1.00 |
| 0.012 | 1.00 |
| 0.016 | 1.00 |
| 0.020 | 1.00 |
(b) Large deflection response
Figure 14 Non-linear response of a stiffened plate. E=2.1\times10^{6} ; v=0.3
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text_image
hinged immovable edge
(a) 4-node shell model
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t R
(b) Axisymmetric model
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line
| Vertical displac. of center | P |
|---|---|
| 0 | 0 |
| 1 | 1500 |
| 2 | 2500 |
| 3 | 1000 |
| 4 | 1200 |
| 5 | 1300 |
| 6 | 1400 |
| 7 | 1500 |
| 8 | 1600 |
| 9 | 1700 |
| 10 | 1700 |
(c) Elastoplastic load-displacement curve
Figure 15 Response of elastic-perfectly plastic circular plate subjected to a concentrated load, P, at its centre. TLF abbreviates use of total Lagrangian formulation and MNO abbreviates use of materially non-linear-only formulation. R=100, t=1; E=2.1\times10^{6} ; E_{T}=0.0 ; \nu=0.3 ; \sigma_{\nu}=1000 . Circular plate response; —, axisymmetric model;
●, 4-node shell model
tive integration displacement models for nonlinear analysis of curved beams, Int. J. Num. Meth. Eng., 17, 615–631 (1981)
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