不同支承对海洋平台模型动力特性参数影响的实验研究

An Experimental Study on the Influence of Dynamic Characteristic Parameters to the Offshore Platform Model with Different Supportings

在比例为1:20的海洋平台模型上,应用随机减量与频谱分析相结合的方法,完成了三种支承条件下测定平台固有频率与阻尼比的实验研究。结果表明:支承条件对海洋平台动力特性参数有明显影响,只有在实际支承条件下实测得到的固有频率与阻尼比才是真实的。随机减量技术只要求测量动力响应,不要求测量引起动力响应的随机激励。因此,应用随机减量技术,可利用自然力(风,海浪)激励,测定平台在实际支承条件下的固有频率与阻尼比。

In combination with random decrement and spectrum analysis, an experimental study,whose scale of the platform model was 1:20, was completed under the condition of three states of supporting. The result shows that the supporting conditions have the distinct influence to the above mentioned parameters. Only the natural frequency and damping ratio measured under the real conditions are truely reliable. Since the technique of random decrement just needs the measurement of dynamic response and has no requirement for the measurement o{ random excitation caused by the dynamk response, so the random decrement technique can be used to measure the natural frequency and damping ratio of the platform by using natural force excitation (wind, sea wave) under the real supporting conditions