基于柔度曲率矩阵的曲面板结构损伤识别方法

Approach of Bending Plate Structural Damage Detection Based on Flexibility Curvature Matrix

为了对船体中曲面板结构的损伤部位准确地进行损伤识别分析,提出了一种基于柔度曲率矩阵的曲面板结构损伤识别方法并进行了仿真分析。按照Kirchhoff薄板假定对板结构进行单元划分,以结构的响应重建柔度矩阵,并通过类曲率半径方法对柔度值的变化进行放大进而得到柔度曲率矩阵。算例分析表明,该方法损伤定位准确并且具有较高的灵敏度,避免了使用原未损结构的模态参数,所需损伤结构的模态少甚至只需一阶模态信息就可有效地进行损伤识别分析。

To detect and analyze the bending plate structure＇s damage part in hull, this paper presents a method of detecting plate structure damage which is based on the flexibility curvature matrix for the simulational analysis. The plate structure is meshed according to Kirchhoff thin sheet assumption. Flexibility matrix can be rebuilt with regard to structure response, and variation of flexibility is amplified through second order differential coefficient to obtain the flexibility curvature matrix. Examples indicate that the method can locate the damages exactly, which is highly sensitive and needn＇t use original undamaged structure＇s mode parameters, and that the damage can be detected with satisfactory precision by a few lower modes even the first mode.