【摘要】 针对海洋平台损伤检测方法中需要未损伤模型参数的不便,提出了一种相对频率变化量的方法。对不同类型构件的损伤及同一类型构件在不同位置损伤的情况,进行结构模态分析,研究平台结构的固有频率对损伤、损伤位置和损伤程度的敏感性,以及平台质量变化对频率的影响。利用两次测量的相对频率变化量,可以发现损伤的存在,并进行损伤的初步定位。更多还原

【Abstract】 Crack detection methods using modal frequencies of a jacket platform are analyzed and improved. The underwater beams are sorted into four groups. The modal parameters for crack detection are calculated numerically when the platform has a crack at different locations in the same group or in different groups. The sensitivities of different modal frequencies to different cracks are analyzed. And the effects of mass change on the frequencies are evaluated. An improved method is introduced to predict the existence and the approximate location of the crack by using relative frequency changes of the damaged platform, without considering the data of an intact structure.更多还原