The damped blades is a nonlinear dynamic system, so its naturalfrequency can be influenced by external force.
与线性动力系统不同，阻尼叶片的频率不再是它的固有特性，其频率受外界激振力的影响。
2
The wind load has recently become a major concern in wind-resistant design of long-span roof structures due to their characteristics: light, flexible, lightly damped, low naturalfrequency and so on.