摘要
为保障在役拱桥吊杆的健康与安全,针对吊杆的多点腐蚀特征,提出了一种基于多点散射回波的无参考腐蚀损伤识别方法。通过引入分形函数模拟钢丝锈蚀表面,建立了多点腐蚀钢丝的有限元模型;采用小波变换提取多点散射回波的多尺度能量谱,并将其作为特征向量构建腐蚀指标,分析了导波频率对腐蚀识别结果的影响,并对某在役拱桥吊杆进行实桥检测和现场开窗验证。结果表明:不同腐蚀程度下,散射回波的多尺度能量谱变化显著,基于散射回波多尺度能量谱的腐蚀指标随腐蚀程度的增加线性上升;随着导波频率的增加,其识别指标的损伤敏感性上升。较10 kHz相比,50 kHz和100 kHz的敏感性系数K值分别增加了6.13%,131.902%;吊杆实测腐蚀指标差异明显,指标值分布在3.91~9.65,吊杆现场开窗检测结果与腐蚀指标识别结果一致。
Here,to ensure health and safety of suspenders of arch bridges in service,aiming at multi-point corrosion features of suspenders,a non-reference corrosion damage identification method based on multi-point scattering echoes was proposed.Firstly,the finite element model of multi-point corrosion steel wire was established by introducing a fractal function to simulate steel wire rusty surface.Then,wavelet transform was used to extract multi-scale energy spectra of multi-point scattering echoes,the energy spectra were taken as feature vectors to construct corrosion indices,and analyze effects of guided wave frequency on corrosion recognition results.Finally,guided waves were used to detect suspenders of a certain in-service arch bridge,and the detection results were verified by destroying local PE(Polyethylene)layers.The results showed that multi-scale energy spectra of multi-point scattering echoes change significantly under different corrosion degrees,corrosion indices increase linearly with increase in corrosion degree;with increase in guided wave frequency,its identification index’s damage sensitivity rises,compared with guided wave frequency of 10 kHz,sensitivity coefficients of 50 kHz and 100 kHz increase by 6.13%and 131.902%,respectively;the actually measured corrosion indices of suspenders are obviously different,and they are distributed in range of 3.91-9.65;detecting results of PE failure tests and recognition results of corrosion indices are consistent.
作者
陈鑫
朱劲松
林阳子
官幼平
CHEN Xin;ZHU Jinsong;LIN Yangzi;GUAN Youping(School of Architecture Engineering,Tianjin University,Tianjin 300072,China;China Railway Bridge Science Research Institute,Co.,Ltd.,Wuhan 430034,China;Guangdong Rongjun Construction Engineering Testing Co.,Ltd.,Guangzhou 528251,China;Shenzhen Cable and Suspender Bridge Engineering Testing Co.,Ltd.,Shenzhen 518000,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第19期295-301,共7页
Journal of Vibration and Shock
基金
国家重点研发计划(2017YFF0108700)
国家自然科学基金(51578370)。
关键词
拱桥吊杆
腐蚀损伤识别
导波
多点散射
suspender of arch bridge
corrosion damage identification
guided wave
multi-point scattering
