基于超声导波检测的角钢型材缺陷特性分析

输电线路铁塔长期暴露在大气环境之中受到腐蚀,会造成角钢型材不同位置出现壁厚减小的情况,严重时可能导致铁塔断裂倒塌.为此,对角钢型材内壁锈蚀情况的检测技术进行探究.首先,对超声兰姆波的传播机理进行分析,确定角钢型材超声兰姆波的检测模态;然后,基于有限元理论对角钢型材进行三维数值建模,通过数值模拟探究了导波在钢材中的传播特...

Analysis of defect characteristics of angle steel based on ultrasonic guided wave detection

The transmission line tower would be corroded due to long time exposure in the atmospheric environment, which results in wall thickness reduction at different positions of angle steel sections and even leads to fracture and collapse. Therefore, the corrosion detection method for the inner wall of transmission line tower needs to be studied. Firstly, the propagation mechanism of ultrasonic Lamb wave is analyzed to determine the frequency detection mode of ultrasonic Lamb wave suitable for angle steel sections. Then, based on the finite element theory, the three-dimensional numerical model of angle steel section is established, the propagation characteristics of guided wave in steel material are explored, and the echo waveform characteristics at the end of angle steel section for different excitation frequencies are analyzed. Finally, the propagation characteristics of ultrasonic Lamb wave in the angle steel section under different defect conditions are obtained by numerical simulation for the angle steel section with corrosion defects at different positions and depths. The results show that the proposed detection method can effectively detect the defects of transmission line tower and provide a reference for practical applications.