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迫切需要研究有效的技术进行结构的健康监测,提高复合结构的安全性和完整性。研究的主要目的是,采用灵敏的压电材料和现代仪器如扫描激光振动计(SLV),以评估基于动力学的复合层板损伤探测技术。采用两个不同的驱动传感器系统测试一个嵌层的E-玻璃/环氧复合板,两个传感器分别为:1)带有PZT(铅-锆酸盐-钛酸盐)调节器的扫描激光振动计(PZT-SLV);2)带有PZT调节器的聚偏二乙烯氟化物(PVDF)传感器。同时进行了有限元分析以补充损伤探测。试验和数值弯曲模型被用于探测剥离的发生、位置和尺寸。采用三种相对新的损伤探测算法(即简化裂隙平滑方法,广义不规则维数方法及应变能方法)分析试验和数值弯曲模型数据以及均荷表面的曲率。损伤探测成果证实PZT-SLV系统更便利和有效,能够扫描到整个试件的大部分点;可直接获得弯曲模型的PZT-PVDF系统,该系统显示对损伤具有良好敏感性。基于三个模式连续利用的GSM,GFD和SEM损伤探测算法及由此引出的ULS曲率,可以成功识别组合板中剥离的发生、位置和相对尺寸。
There is an urgent need to study effective technologies for structural health monitoring and to improve the safety and integrity of composite structures. The main objective of the study was to use a sensitive piezoelectric material and modern instruments such as the Scanning Laser Vibrometer (SLV) to assess kinetic-based composite plate damage detection techniques. Two different drive sensor systems were used to test a layered E-glass / epoxy composite panel with two sensors: 1) scanning laser vibrations with a PZT (lead-zirconate-titanate) (PZT-SLV); 2) Polyvinylidene fluoride (PVDF) sensor with PZT regulator. At the same time, finite element analysis was performed to supplement the damage detection. Experimental and numerical bending models were used to detect the occurrence, location and size of the peel. Three relatively new damage detection algorithms (simplified crack smoothing method, generalized irregular dimension method, and strain energy method) were used to analyze the experimental and numerical bending model data and the mean surface curvature. The results of the damage detection proved that the PZT-SLV system was more convenient and effective and could scan most of the entire specimen. The PZT-PVDF system, which can directly obtain bending model, showed good sensitivity to damage. Based on the three modes of continuous use of GSM, GFD and SEM damage detection algorithms and the resulting ULS curvature, the occurrence, location and relative size of the peel in the composite panel can be successfully identified.