Large-span steel truss girder bridge whole joist full-welding joint welding method

Abstract

The invention relates to a large-span steel truss girder bridge whole joist full-welding joint welding method. The method comprises the following steps that A upper chords, lower chords, upper chord whole joint boards, lower chord whole joint boards, brace covering boards and brace webs are prefabricated; B the prefabricated chords are assembled in a welded mode to constitute whole joists; C over-welding hole blocking boards and outer reinforcing boards are welded; D ultrasonic hammering is conducted on weld joints. The method greatly reduces the usage quantity of high-strength bolts when the joists are assembled on a construction site, and not only reduces weight of the whole structure, but also reduces the work amount for screwing the bolts. According to the method, a welding sequence, welding materials, a welding standard and the like are provided, deformation produced during welding is reduced, the sizes of the chords are guaranteed, and it is guaranteed that the mechanical property of weld joint metal meets requirements. In order to guarantee fatigue strength of the whole joint welding structure, the invention further provides a technology for weld joint over-welding hole blocking and outer reinforcing board welding. By means of ultrasonic hammering, fatigue strength of the whole joist full-welding joint weld joints is enhanced.

Description

Technical field [0001] The invention relates to a method for full-welded joint welding and post-welding reinforcement of integral trusses of a large-span steel truss bridge, belonging to the technical field of railway bridge welding. Background technique [0002] At present, the methods used in the erection of steel bridges at home and abroad are basically two types: bulk assembly and segment hoisting. Affected by the lifting capacity of cranes, the railway truss girder bridges built in the early days in China basically used scattered assembly, and the on-site jointing of rods and bolts were a lot of work, high-altitude construction, and poor operating environment. With the improvement of manufacturing technology, erection technology and crane lifting capacity, the Chongqing Caiyuanba Yangtze River Bridge and Wuhan Tianxingzhou Yangtze River Bridge built in China in recent years have adopted the method of segmental lifting and erection. The use of segmental hoisting, a large num...

AI Technical Summary

Problems solved by technology

Affected by the lifting capacity of the crane, the railway truss bridges built in the early stage in China were basically assembled in pieces. The workload of splicing rods and screwing bolts on site was large, and the construction was carried out at high altitude, and the working environment was poor.

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