振动模态分析法在单立柱海洋平台上应用

Application of vibration modal analysis in single pillar offshore platform

提出联合经验模态分解和二次时频分布的参数识别方法。将结构的响应信号用经验模态分解的方法分解为单频率响应的振动信号,进而计算模态频率和模态阻尼,用Choi-Williams分布计算模态振型。对单立柱海洋平台的计算表明,该方法能比较理想地识别出结构的模态参数,且具有较强的抗噪能力。

A method of identifying parameters is presented by joining Empirical Mode Decomposition （EMD） and time-frequency distribution. A muti-degree system is decomposed to single-frequency vibration mode responses and then the frequencies and dampings are calculated. The mode shape is identified by Choi-Williams distribution. An example of a single pillar platform shows that the method can identify the mode parameters well, and has good anti-noise ability.