基于超声波换能器的钢筋机械损伤与锈蚀损伤检测及其对比研究

Ultrasonic transducer-based mechanical damage and rust damage detection of steel bars and comparative study

超声导波检测技术有检测耗时少、覆盖范围大等优点.为检测钢筋混凝土结构中钢筋损伤,采用超声波换能器研究不同深度和位置的机械损伤对超声导波传播的影响,建立损伤程度与导波特征关系.通过反射系数C定量分析损伤程度,并结合损伤反射回波判断损伤位置.在钢筋点锈蚀以及均匀锈蚀损伤检测中,锈蚀程度达到最大时,L波实际波速分别为4738.1 m·s^(-1)和5069.7 m·s^(-1),以此区分锈蚀损伤与机械损伤,最后基于小波变换的时频分析判断损伤状况.研究成果可为钢筋损伤检测研究提供参考.

Ultrasonic guided wave inspection technology has the advantages of less detection time and wide coverage.In order to detect the damage of reinforcing steel in reinforced concrete structures,the ultrasonic transducer was used to study the effect of mechanical damage at different depths and locations on the propagation of the ultrasonic wave guide.The relationship between the degree of damage and the wave guide characteristics was established.The degree of damage was quantified by the reflection coefficient C,and the location of the damage was determined by combining the reflected echo of the damage.The actual L-wave velocities were 4738.1 m·s^(-1) and 5069.7 m·s^(-1) when the corrosion level reached the maximum in the spot corrosion and uniform corrosion damage detection,respectively,which could be distinguished from the mechanical damage.Finally,the wavelet transform-based time-frequency analysis was used to determine the damage condition.The results of this study can be used as a reference for rebar damage detection.