有限观测绝对加速度响应下剪切框架在未知地震作用下损伤诊断

针对框架结构的绝对加速度响应部分观测、地震作用未观测的情况，提出一种多层剪切框架结构诊断的方法。该方法先依次采用扩展卡尔曼估计和递推最小二乘对一层以上结构的扩展状态向量和未知作用力进行递推；然后利用结构频率特征方程，对第一层的结构参数进行估计；最后基于数值求解一阶微分方程，识别未观测的地震荷载。算例表明, 该方法能够很好识别出结构参数和地震输入，通过跟踪结构刚度参数的退化，对未知地震作用下结构损伤进行诊断。

Structural damage detection of a shear building under unknown earthquake excitation with limited observations of absolute acceleration reponses

Here,a method was proposed for structural damage detection of a multi-story shear building under unknown earthquake excitation with partial observations of absolute acceleration responses.Based on the extended Kalman estimator and the least square estimation adopted sequentially,the structural parameters above the first story of the building could be identified.Then,the structural parameters of the first story were identified with the frequency equation.Finally,the unknown earthquake excitation identified via the numerical solution to a first-order differential equation.It was shown with a numerical example that the proposed method can identify structural parameters and earthquake excitation with good accuracy;structural damage under unknown earthquake excitation can be detected by tacking degradation of structural stiffness parameters.