Nonlinear Vibration Responses of a Circular Cylindrical Tank with Water on Shaking Table Driven by Periodic Force

提出了一种新的圆柱形贮箱响应测量方法。在Windows操作系统下，控制三块AD板，得到5个贮箱的位移响应和32个圆形贮箱的应变响应。新的测量系统能够以比传统系统快36倍的速度获得数字响应数据。利用该系统对带盖圆柱壳进行振动模态分析，利用电磁驱动器在正弦周期力作用下驱动带盖圆柱壳振动台。在一定的外频率和振动台加速度作用下，结构存在失稳区域，分支在此区域发生较强的亚谐振动。我们试图分析亚谐振动的振动模式。在每两个不同高度的水箱中，我们得到了16个应变数据。每16个数据用于分析周向振型，两个不同高度水平的数据用于分析发电机的方向振型。分析得到的振动模态响应曲线如图所示。

A new measuring response of circular cylindrical tank with water was developed. Under the OS of Windows, three AD boards are controlled to get 5 points of displacements of the tank and 32 points strain responses of the circular tank. The new measuring system enables to get digital response data 36 times faster than the conventional one. We used the new system to analyze the vibration modes of the tank for the direction of the generator.A cylindrical shell with a lid was set on a shaking table driven by an electronic-magnetic actuator with sinusoidal periodic force. There are some instability region under some external frequency and shaking table acceleration, where strong sub-harmonic vibrations happen to branch. We tried to analyze the vibration mode of the sub-harmonic vibrations. We get 16 strain data at each two different height of the tank. Each 16 data were applied to analyze the vibration mode for circumferential direction and two data obtained by two different height levels were used to analyze the mode for direction of the generator. The response curves of the analyzed vibration modes were shown as figures.