船舶结构动载试验的基于参考测点随机子空间法

文章提出了基于参考点的随机子空间船舶模态参数识别方法.该方法直接根据环境激励下测得的输出响应来构建Hankel矩阵,并通过QR分解技术对数据进行精简,再对投影矩阵进行奇异值分解(SVD)来剔除噪声,最后识别出结构的模态参数.它不受FFT(傅立叶变换)的影响,识别速度快,精度高.对于需快速识别船舶结构的模态参数,检测其可能存在的损伤,建立起预警及适时维修机制提供了有效手段.

Method of reference based stochastic subspace identification is discussed by dynamic load testing of ship structure

A method of reference based stochastic subspace identification(SSI) is discussed in this paper. In this method, the output measurements from ambient excitation are gathered directly in a block Hankel matrix. Then SSI reduces data through QR factorization and applies SVD to eliminate noise, at last the structural modal parameters are identified. SSI can't affected by FFT, which is one of time domain method with fast computation rate and high identification accuracy. Therefore a predicting and warning and timely maintaining system based on identifying the modal parameters and inspecting damages of the ship structures is developed which can help to eliminate hidden troubles and avoid the occurrences of catastrophic accidents.