为解决港珠澳大桥8 mm厚U肋角焊缝探伤问题，进行了U肋角焊缝超声相控阵探伤技术分析，通过焊接试件的探伤试验，考察了该焊缝超声相控阵探伤的检测精度，提出的U肋角焊缝的超声相控阵探伤检测及判定方法，可以指导港珠澳大桥U肋角焊缝的无损检验工作，同时为其它桥梁此类焊缝的无损检验提供借鉴。主要取得了以下两项成果：一是根据U肋角焊缝的缺陷特征，建立了焊缝探伤数学模型，并在此基础上提出了基于超声相控阵技术的缺陷信号图像端点读值法，简化了探伤检测过程，提高了检测精度；二是提出了基于检测误差的U肋角焊缝探伤判定方法，较好地解决了焊缝探伤中的漏判与误判问题。

Researches were carried out for the technology on welding bead of ultrasonic phased array testing of U rib fillet weld in order to solve the issue of it on the thickness of 8mm on U rib fillet weld, which adopted the method of welding specimen flaw detection by inspecting and observing the precision leads to a conduction of the work in Hong Kong-Zhuhai-Macao Bridge, and the like. This article gets some creativity as below: Firstly, a mathematical model of welding nondestructive as per the flaw characterization of U rib fillet weld was built up, proposing a flaw signal image endpoint read value method based on it. The above mentioned method actually leads to simplify the procedure and improve the precision. Secondly, a method of judgment in U rib fillet weld detection based on error-detecting was proposed, which solved the issue of false negatives or false positives among welding nondestructive testing.