超声相控阵在桥梁锚具检测中的影响因素分析

摘要

针对桥梁锚具曲面厚壁结构特点,为改善超声波检测的声束可达性和检测覆盖率,采用超声相控阵技术对桥梁锚具进行检测.采用与桥梁锚具相同材质和生产工艺制作对比试块,以圆形横通孔为研究对象,分析表面曲率、探头频率、探头类型、缺陷直径和缺陷深度对缺陷检测能力的影响.结果表明,缺陷检测灵敏度随表面曲率增加而降低、随缺陷直径增加而增大、随缺陷深度增加而降低,圆弧探头的耦合性可有效改善表面曲率对缺陷检测能力的影响.%The bridge anchorages are usually curved and thick-walled structures.In light of these characteristics, the anchorages are inspected by the ultrasonic phased array technique, with the intension of improving the accessibility of acoustic bonds and the testing coverage rate of the ultrasonic inspection.Testing samples that are made of the same materials and by the same processing technique to those of the bridge anchorages were prepared.The round transverse through holes were taken as the subjects of the study, to analyze the influence of a series of factors on the defect inspection capacity of the method, including the surface curvature, frequency and type of the detectors as well as the diameter and depth of the defects.The results of the analysis reveal that the defect inspection sensitivity declines as the surface curvature increases, rises as the diameter of the defects enlarges, and falls as the defect depths grows.The coupling of the arc probes can effectively ameliorate the influence of surface curvature on the defect inspection capacity of the technique.