Order number | Natural frequencies (HZ) | Modes description |
1 | 2.2084 | The left side―backward, the right side―forward. |
2 | 2.2084 | The left and right―forward, the middle part―backward, accompanied with torsional vibration of Fishbelly steel truss. |
3 | 2.4213 | The left, right and middle parts, in their own range, do forward and backward antisymmetric vibration. |
4 | 2.4218 | Middle part―backward, the left and right parts―forward, and the external side vibrates forward. |
5 | 2.8850 | Middle part of right side―backward and the two sides―forward; middle part of left side―forward and the two sides―backward. |