θ (˚) | Theory | Eigenvalue | Transient | Nonlinear (Imperfection) | Nonlinear |
0 | 4225.1 | 4482.4 | 4221 | 4130.98 | 4844.52 |
5 | 4288.5 | 4542.9 | 3102.72 | 3087.43 | 3102.9 |
10 | 4490.2 | 4737.8 | 2805.12 | 2801.46 | 2805.33 |
15 | 4865.1 | 5111.9 | 2773.92 | 2772.19 | 2774.4 |
20 | 5489.5 | 5758.2 | 2995.92 | 2994.05 | 2996.01 |
25 | 6526.5 | 6869.0 | 3616.08 | 3606.86 | 3616.1 |
30 | 8366.0 | 8896.4 | 5160.6 | 5132.29 | 5160.85 |
35 | 12183.5 | 13197.0 | 9781.2 | 9681.77 | 9782.44 |
40 | 23814.6 | 26549.0 | 12463.2 | 12208.8 | 12467.2 |