针对大型的碳纤维复合材料机翼盒段壁板结构,研究采用光纤布喇格光栅测量结构应变场分布,提出采用最小二乘支持向量机(LS—SVMs)建立应变场-损伤非线性黑箱模型辨识结构损伤法,对典型的飞机碳纤维复合材料盒段壁板结构进行健康监测研究。针对大尺寸带有加强桁条和螺钉通孔的复杂结构盒段壁板试件,建立了7个点的布喇格光栅应变测量网络测量试件有代表性区域的应变场。通过施加280个不同的点载荷模拟损伤,建立应变场与损伤的非线性映射关系黑箱模型;采用LS-SVMs的黑箱模型辨识法对应变场进行有效辨识,准确地判别出280种结构损伤的位置和程度。
For the complex structure and anisotropy nature of the carbon fiber composite material wing box,a way of structure health monitoring(SHM) of wing box using fiber bragg grating has been presented in this paper. The strain field-damage nonlinear black box model was established based on LS-SVMs to identify the structural damage. For the big-size complex structure box wainscot with enheneed purtins and the screw hole,the strain field in the representative area of the sample has been measured by establishing the Bragg grating measuring network with 7 points. By applying 280 different poing loadings to simulate the damage, the black box model of the mapping relationship between the strain field and the damage has been established. The experiment result showed that the strain field could be identified effectively by using LS-SVMs black box model. The 280 structual damage locations and the damage degree have been identifed accurately.