基于静动力凝聚及扩展卡尔曼滤波的连续梁桥损伤识别  

DAMAGE DETECTION FOR CONTINUOUS GIRDER BRIDGE BASED ON STATIC-DYNAMIC CONDENSATION AND EKF

作　　者：何浩祥[1] 吕永伟[1] 韩恩圳[1] 

机构地区：[1]北京工业大学工程抗震与结构诊治北京市重点实验室,北京100124

出　　处：《工程力学》2015年第7期156-163,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(51108009;50878010);高等学校博士学科点专项科研基金项目(20111103120022)

摘　　要：以卡尔曼滤波算法为代表的物理参数识别方法在结构损伤识别方面得到广泛应用,但限于状态方程的复杂性,大部分应用集中在具有平动自由度的剪切型建筑结构模型,且一般需要较完备的激励和响应信息。利用静力凝聚方法消去转动自由度以建立力学模型,并提出考虑Rayleigh阻尼的动力凝聚方法,实现了较复杂连续梁桥有限元模型的等效简化。针对桥梁检测及健康监测需求,提出了利用锤击产生自由振动的激励方式进行连续梁桥扩展卡尔曼滤波在线损伤识别方法,从而克服了传统方法需要复杂激励信号的不足。以一座三跨连续梁桥为例进行了仿真分析,识别出了不同位置的刚度和阻尼物理参数,参数识别结果具有较高精度和抗噪性,收敛速度快,证明该方法有效可行。As a classical method of physical parameter identification, Extended Kalman tllterlng （t~） algorithm is widely used in structural damage detection. However, due to the complexity of the state equations, most applications focus on the shear structure model with translational degrees of freedom considered only, and the comprehensive excitation and response signals are generally needed. Recognizing that the rotational degrees of freedom can be eliminated by the static condensation method, this paper proposes the dynamic condensation method considering Rayleigh damping, in order to establish the equivalent and simplified model for continuous girder bridges. According to the requirements of bridge inspection and health monitoring, the online and convenient damage detection method based on Extended Kalman filtering is presented, and the free vibration is generated by one hammer action, so that the deficiency of the traditional method needing complex excitation information is overcame. Taking a three-span continuous girder bridge as an example, the corresponding stiffness, the damage location and degree and the damping parameter were identified accurately by the proposed method, showing that the proposed method, with fast convergence speed, is feasible for the case of dynamic signal with high noise-signal ratio and practical engineering.

关 键 词：扩展卡尔曼滤波 损伤识别 静力凝聚方法 连续梁桥 健康监测 

分 类 号：U448.21[建筑科学—桥梁与隧道工程] TU317[交通运输工程—道路与铁道工程]