智能材料结构中压电元件局部脱胶损伤特性研究

【作者】 蒋雅娜；

【导师】 王帮峰；

【作者基本信息】 南京航空航天大学 ， 测试计量技术及仪器， 2004， 硕士

【摘要】 传感器与复合材料结构基体之间的局部开胶是智能结构失效的一种重要形式。脱胶损伤会导致传感器对结构动态响应的感知出现误差并影响整个结构的动态特性，从而降低了智能结构的性能甚至导致智能结构的失效。本文以表面贴有压电陶瓷元件的复合材料为试验对象对传感器局部脱胶损伤的特性进行了研究。 本文首先对当前智能材料结构以及结构健康监测技术的研究状况和发展趋势进行了总结与综述，并由此得出对传感器局部脱胶损伤进行研究是非常必要的结论。其次，介绍了有限元分析法、试验模态分析法和黄氏变换(HHT)的原理，为后面的试验分析奠定了理论基础。再次，采用压电元件做传感器的复合材料悬臂梁结构为试验对象，利用模态分析、HHT变换的方法，对压电元件与复合材料之间的脱胶损伤对结构动态特性的影响进行试验研究。研究结果表明，传感器局部开胶对结构的瞬时频率和模态频率以及阻尼比均有明显的影响。与模态分析方法相比，HHT分析的结果准确稳定，变化趋势清晰明显而且具有明显的物理含义。最后，对含有脱胶损伤的平板型结构也进行了初步的试验研究。对其表面粘贴的含有脱胶损伤的压电传感器响应信号进行了时域、频域的分析。试验结果表明，脱胶损伤对响应信号的幅值和主频点以及主频点的幅值均有影响。更多还原

【Abstract】 Partially debonding at the transducer-structure interface is a major factor significantly altering the dynamic response of smart structures, hence the ineffectiveness of the structures. This paper presents an experimental investigation conducted to analyze this effect of the transducer debonging .This paper starts with a brief introduction of the birth and development of Smart Materials and Structures and Health Monitoring, which serves as a prelude to the research subject - partially debonding at the transducer-structure interface. Then, it deals with the theory of the Finite Element, Experimental Modal Analysis and Hilbert Huang Transform, which forms the theoretical groundwork of the following experimental investigation aiming at analyzing the effect of the transducer debonging on the dynamic response of composite laminated cantilever beam.The research results show that transducer partially debonding results in clear change of instantaneous frequencies, mode frequencies and damping ratio of the structures. HHT is more effective than experimental modal analysis and can give a more clear physically meaningful interpretation to the structure response.Finally, an experimental research for composite laminated flat is carried out to analyze the signal of piezoelectric plat with partially debonding at the transducer-structure interface. The experiment has validated that transducer partially debonding results in clear change of the response signals’ amplitudes, main frequency points and amplitudes of the main frequency points.更多还原