针对TOFD(超声波衍射时差法)检测钢结构桥梁对接焊缝内部缺陷时，缺陷类型难以准确判别的问题，设计制作了12块含有典型焊接缺陷的人工模拟试件，并进行TOFD检测，对比分析了焊缝缺陷的TOFD-D扫图像特征。试验结果表明，不同类型缺陷的TOFD-D扫图像特征具有明显差异，通过分析D扫图像的纹理、形状及走向，可实现基于TOFD-D扫图像特征的对接焊缝典型缺陷类型判定。

Aiming at the difficult problem of the TOFD(time of flight diffraction)method testing the internal defect types of the steel structure bridge butt welds, 12 artificial simulation specimens containing typical weld defects were designed and produced, and TOFD testing was carried out, and the weld defects TOFD-D were compared and analyzed. Scan image features. The test results show that different types of defects have obvious TOFD-D scan image feature differences. By analyzing the texture, shape and direction of the D scan image, the typical defect types of butt welds can be determined based on the TOFD-D scan image features.