基于频响函数虚部的梁结构损伤检测  

Damage detection for a beam based on imaginary part of its FRF

作　　者：张宇飞[1,2] 王山山 

机构地区：[1]河海大学力学与材料学院,南京210098 [2]中国电建集团华东勘测设计研究院有限公司,杭州311122

出　　处：《振动与冲击》2018年第2期38-42,共5页Journal of Vibration and Shock

摘　　要：提出了基于频响函数虚部的梁结构损伤检测方法,依据模态曲率提出了判别损伤的指标CIFF。该指标仅需要利用结构损伤后的随机振动响应信息,避免了需要获得结构未损伤前的模态信息的弊端,并且该方法在一定程度上考虑了系统误差与噪声干扰。通过一钢质悬臂梁的动力试验,验证了该方法对判别梁结构单裂缝损伤和多裂缝损伤的有效性。结果表明,该方法不仅能检测出损伤的位置,并且能表征损伤的程度。对于实际工程中的梁结构损伤检测研究具有一定的意义。A damage detection method for a beam based on imaginary part of its frequency response function( FRF) was proposed. According to the beam's modal shape curvatures,an index called CIFF to judge its damage was defined. This index needs to use the beam random vibration response information after its damage to avoid the disadvantage of needing the modal information of the beam before its damage and consider the beam system error and noise disturbance to a certain extent. Through a dynamic test of a steel cantilever beam,the effectiveness using this method to judge the beam's single-crack damage and multi-crack damage was verified. The test results indicated that the proposed method can not only be used to detect damage's position,but also reflect its level. The results provided a reference for the damage detection of real beam structures.

关 键 词：频响函数 模态曲率 损伤检测 动力响应 动力试验 

分 类 号：TU317.1[建筑科学—结构工程]