随机激励下的线性结构系统局部刚度参数识别

基于线性随机系统理论中的输入和输出随机信号的方差固有关系、变分原理和多参数优化方法,发展了一种新的识别线性结构系统局部刚度大小的方法。验证算例表明,这种方法估算的局部刚度的大小与真实的结果非常接近,精度很高。经过3次迭代之后,最大的相对误差约为1%;经过4次迭代之后,相对误差减少两个数量级,小于0.012%;经过5次迭代之后,误差几乎为零。

Method for Identifying Local Stiffness of Linear Structures Under Random Excitations

A new method to identify the magnitude of the local stiffness in the linear structural system under random excitations was developed based on the natural relationship of the variances between input excitations and the output responses,variation principle and multi-parameter's optimization method.An illustration example shows that the estimation results are agreed well with the exacted values.The maximum relative error is about 1% after 3 time iterated process,and it is less than 0.012% after 4 time iterated process and it is almost equal to zero after 5 time iterated process.