Collaborative improvement path of strength and toughness of high-performance bridge steel welded joints

China’s high-speed rail development leads the world, vigorously promoting the construction of steel structure railway bridges. At the same time, research and application of high-performance bridge steel have also made significant progress. In engineering applications, the performance of high-performance bridge welded joints runs through the entire life cycle of design, construction, and service, and is a key issue of concern for researchers. In terms of the mechanical properties of the joint, combining reasonable composition design and processing technology, it is not too difficult for the strength of high-performance steel welded joints to meet the design requirements. In contrast, how to improve the toughness of the joint while maintaining high strength has become a bottleneck in solving the problem. In depth research from the perspective of weld formation, taking into account the coupling effects of factors such as steel plate basic performance, welding materials, and welding processes, and organically linking microstructure and performance, is an important way to solve the strengthening and toughening of high-performance bridge steel welded joints. Through selecting appropriate welding materials and controlling welding heat input reasonably, the synchronous improvement of weld strength and toughness of high-performance bridge steel has been achieved, improving joint performance and laying the foundation for related applications