基于岭估计和L曲线的损伤识别技术研究

为了解决结构损伤方程求解的可靠性问题，提出了基于岭估计和L曲线的损伤方程求解方法。首先描述了基于模态应变能灵敏度的结构损伤方程，然后考虑测量噪声等因素易造成病态的损伤方程问题，提出了采用岭估计求解结构的损伤方程，并利用L曲线确定最优的岭参数，最后建立了损伤估计值的修正方法。数值仿真结果表明，基于修正的岭估计和L曲线方法可以较为精确地识别出损伤的位置和程度，而且其定量识别结果明显好于基本的岭估计和L曲线方法以及一般的截断奇异值分解法。

Structural damage identification method based on ridge estimation and L-curve

In order to solve the reliability problem of structural damage equation, a damage detection method based on ridge estimation and L-curve is presented. First, a structural damage equation based on modal strain energy sensitivity is given out. Then, considering that measurement noise will cause the ill-posed equation problem, ridge estimation is utilized to solve the damage equation and L-curve is utilized to identify optimal ridge parameter. Finally, an improved ridge estimation method is proposed to enhance the identification precision. Simulation results demonstrate that the proposed ridge estimation and L-curve method can detect structural damage locations and extent with good accuracy, the quantification results of the proposed method are obviously better than those of the basic ridge estimation and L-curve method and the truncated singular value decomposition method.