摘要
目的绘制层状管道结构导波的频散曲线,提出一种利用压电超声导波层状管道结构损伤识别方法.方法利用Navier方程及边界条件建立频散方程并进行数值求解,分别绘制出空管和充液两种情况下的导波频散曲线.为了验证理论分析结果,利用压电导波试验方法,对一个长2 m的层状空管和层状充液管道中的人工周向缺陷进行识别.结果导波的频散和衰减程度较弱的L(0,1)模态适合于层状充液管道中的损伤识别.随着导波频率的增加,频散效应逐渐增加,损伤识别能力也逐渐下降.对于充液管道,导波能量会通过液体中传播,降低损伤识别的精度.结论在对层状充液管道进行损伤识别时,应根据频散、衰减和导波结构等传播特性选取合适的纵向模态.利用压电导波进行层状管道结构损伤识别是十分有效的.
The purposes of the paper is to draw dispersion curves of guided waves in layered pipe- line structures （LPSs）, and propose a damage identification method for LPSs using piezoelectric guided waves. The Navier＇s Equation and boundary conditions are used to set up the dispersion e- quations which will be solved by numerical method. Two kinds of guided wave dispersion curves for the given LPS with or without liquid are drawn respectively. To verify the numerical results, an experiment for a 2m layered pipe with the artificial circumferential defects is conducted by utilizing the longitudinal modes. The results show that the L（0,1 ） mode longitudinal guided wave which has the properties of weak dispersion and energy attenuation is suitable for the damage identification of the LPSs. The dispersion effect will gradually increase and the damage identification capacity will decrease as increasing the frequency of the guided waves. For the pipe filled with liquid, the energyof the guided wave will partly propagate through liquid which will decrease the precision of dam- age identification. A suitable longitudinal mode of guided wave should be selected according to the dispersion effect, energy attenuation, and structure of the guided waves during damage detection. The proposed method in the paper is quite effective for the damage identification of LPSs using pi- ezoelectric guided waves.
出处
《沈阳建筑大学学报（自然科学版）》
CAS
北大核心
2016年第4期619-627,共9页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金项目(51278313)
辽宁省自然科学基金项目(2015020595)
关键词
层状充液管道结构
压电超声导波
纵向模态
频散方程
损伤识别
layered liquid-filled pipeline structure
PZT-based ultrasonic guided waves
longitudi-nal mode
dispersion equation
dispersion curve
作者简介
阎石（1962-），男，教授，博士研究生导师，主要从事结构健康监测研究．
