natural frequency of bridge span

例句：

1. 1. The natural frequency of thebridge is critical for its stability.
   桥梁的自然频率对于其稳定性至关重要。
2. 2. The engineers were trying to determinethe natural frequency of the structure.
   工程师们试图确定结构的自然频率。
3. 3. Thevibration caused by the wind can be usedto calculate the natural frequency of the bridge.
   由风引起的振动可以用来计算桥梁的自然频率。