为了满足海洋平台结构健康监测和损伤识别的要求,提出了一种以协调模态可观测性与损伤可识别性为目标的传感器优化布置方法。首先根据结构运动方程,利用损伤导致结构响应的变化,推导了结构响应与模态、损伤灵敏度的近似解析解。其次,建立包含模态信息和损伤灵敏度信息的传感器优化数学模型。最后利用奇异值分解方法,发展了一种以信息矩阵最大和条件数最小为目标的迭代算法。海洋平台立管的数值算例表明:该方法能够为海洋平台立管的健康监测提供可行的布点方案。
To meet the requirement of structural health monitoring and damage detection on riser at offshore platform,a method for optimizing sensor locations based on the harmony between damage identifiability and modal observability is presented in this paper.Firstly,accounting for the structural response changes caused by structural damage,the relationship between the structural response with structural modal and damage sensitivity is deduced from the structural motion equation by a quasi-analytical mode.Secondly,a mathematical model is set up including the information of mode independence and damage sensitivity.Finally,Using the technique of singular value decomposition,an iterative algorithm for optimum sensor placement is developed with the criterion of minimum condition number of coefficient matrix and maximum norm of the fisher information matrix.A case study of numerical modeling on the riser at an offshore platform indicates that this method can provide a feasible set of locations for the health monitoring on riser at offshore platform.