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Natural periods and vibration modes.
| Mode shape | original structure | strengthened structure | ||
|---|---|---|---|---|
| period | Characteristics | period | Characteristics | |
| The first mode | 2.92 | Y-direction translation | 2.61 | Y-direction translation |
| The second mode | 2.45 | X-direction translation | 2.44 | X-direction translation |
| The third mode | 2.11 | twisting | 1.84 | twisting |
