基于修正模态应变能指标的板结构损伤定位

为解决模态应变能方法识别中产生的"邻近效应"问题，提出基于修正模态应变能指标的板结构损伤定位方法.该方法首先利用邻近测点的应变能变化相对大小计算权重系数，再根据权重系数对测点相应区域的应变能进行重新分配.此外，通过定义的损伤辨识度指标研究噪声对损伤定位结果的影响.为验证本文所提方法的可行性和有效性，以一个四边简支板为数值算例.算例结果表明，本文方法对于点状、块状和带状损伤都可以实现准确定位，且具有良好的抗噪性.

THE DAMAGE LOCALIZATION FOR PLATE STRUCTURES BASED ON MODIFIED MODAL STRAIN ENERGY INDEX

In order to deal with the "vicinity efiect" in the damage localization of plate structures, this paper proposes a method based on the modifled modal strain energy. Firstly, the relative strain change at adjacent points are used to calculate the weight coe-cients, Then the strain energy in the corresponding area is redistributed according to the weight coe-cients. By deflning a damage difierentiation degrees index, the influences of the noise on the damage localization can be evaluated. To verify the feasibility and the efiectiveness of the proposed method, a four edge simply supported plate is used as a numerical example. It is shown that the proposed method can realize an accurate damage localization in dot, block and strip damage cases, with a good anti-noise capability.