利用模态柔度曲率差识别框架的损伤  

DAMAGE EVALUATION OF FRAMES BY MODAL FLEXIBILITY CURVATURE

作　　者：曹晖[1] 张新亮[1] 李英民[1] 

机构地区：[1]重庆大学土木工程学院,重庆400045

出　　处：《振动与冲击》2007年第6期116-120,124,共6页Journal of Vibration and Shock

摘　　要：采用结构模态参数进行损伤识别是研究较早,应用较多的无损探伤检测方法。提出了一种称为模态柔度曲率差的损伤检测指标。该指标利用模态柔度,不仅比频率和振型更敏感,而且对高阶模态的依赖大为减小。此外,曲率的采用也增加了其对损伤的敏感程度。对两个框架有限元模型进行了分析,详细比较了该指标和振型曲率改变率等其它一些指标在不同的损伤分布和损伤程度下的损伤识别效果,发现模态柔度曲率差识别效果最好,结果最稳定。A new indicator called modal flexibility curvature(MFC)is put forward to evaluate structural damage,which is much more sensitive and relies much less on higher modes parameters.The advantage of modal flexibility and the nature of curvature both make MFC more sensitive to damage.Two FEM models of moment-resistant frames are built and modal parameters in three damage simulation cases are extracted to construct MFC.Moreover,the modal curvature index and two other indicators are also deduced.Subsequently,the abilities of damage evaluation are compared in detail among the four indicators.It is found that MFC can always give more satisfactory results than the other three indicators,irrespective of the damage location and severity.

关 键 词：损伤识别 框架 模态柔度 振型曲率 模态柔度曲率差 

分 类 号：TU311[建筑科学—结构工程]