摘要
结构损伤识别是结构健康监测的一个重要项目。近年来,基于结构振动实测数据的系统辨识和损伤识别技术得到了广泛深入的研究。通常情况下,结构损伤可以透过结构物理参数的改变来预知,比如刚度的骤变。采用自适应二次误差平方和(adaptive quadratic sum-squares error,AQSSE)方法识别结构参数的变化并由此判断结构的损伤。在该方法中,运动状态方程被视为一种约束并用来直接估计未知的参数,最终得到未知参数的解析递归解。同时为了确定时变结构系统的参数,使用了最新的追踪技术以便在线追踪结构的参数变化。针对非线性迟滞结构和平面薄壁结构的仿真结果表明该方法具有较强的追踪能力,能较好地识别时变结构的参数,并由此检测结构的损伤,包括损伤发生的时刻以及损伤的位置和程度。上述结论证明了该方法用于结构损伤识别是可行且有效的。
The identification of structural damage is an important objective of health monitoring for civil infrastructures. System identification and damage detection based on measured vibration data have received intensive studies recently. Frequently, damage to a structure may be reflected by a change of some system parameters, such as the degradation of the stiffness. In this paper, an adaptive tracking technique, Adaptive quadratic sum-squares error (AQSSE) approach, was adopted to identify the structural parameters and their changes when vibration data involve damage events. In this approach, the state equation of motion is considered as a constraint, and the unknown parametric vector is estimated di- rectly. New analytical recursive solutions for the unknown parameter will be derived and presented. Further, an adaptive tracking technique recently proposed will be implemented in the proposed AQSSE approach to identify the time-varying system parameters of the structure and track the variance of structural parameter on-line. Simulation results for tracking the parametric changes of nonlinear hysteretie and trussed construction are presented to demonstrate the method presen- ted has the capability of tracking the time-varying parameters and detecting the damages, including the damage location and severity which further demonstrate the application and effectiveness of the proposed technique in detecting structural damage, using measured vibration data.
出处
《国外电子测量技术》
2017年第4期66-70,90,共6页
Foreign Electronic Measurement Technology
关键词
二次误差平方和
参数估计
追踪
损伤识别
quadratic sum-squares error
parameter identification
tracking
damage identification.