【摘要】 在特定工况下会出现无法将超声换能器放置在杆状构件底面完成常规检测的问题，如服役桥梁的平行钢丝构件、装配式建筑中灌浆套筒内的插入钢筋。为了提高超声导波技术的适用性，提出了将频率为50 kHz的自发自收式干耦合横波超声换能器置于杆状钢丝侧面进行长度检测及缺陷定位的方法。结合理论分析、仿真模拟和试验验证开展研究，结果表明：干耦合横波超声换能器的最优激发角度为90°，即激发方向垂直钢丝轴向；对于不同长度和不同缺陷位置的钢丝，长度检测和缺陷定位的仿真及试验结果的预测相对误差均小于2%。更多还原

【Abstract】 Under certain working conditions, it is impossible to place the ultrasonic transducer on the bottom surface of the rod-shaped component to complete the defect inspection, such as the parallel steel wires of the bridge and the inserted steel bar in the grouting sleeve in prefabricated building. In order to improve the applicability of ultrasonic guided wave technology, a method of length detection and defect localization is proposed by using a 50 kHz drycoupled ultrasonic shear wave transducer. Combining theoretical analysis, simulation and experimental verification,the results show that the optimal excitation angle of the transducer is 90°, that is, the excitation direction is perpendicular to the axis of steel wire; the relative errors of both simulated and experimental results are less than 2%for steel wires with different lengths and different defect locations.更多还原