Two-sided welding method for U-shaped ribbed slab unit welding seam

Abstract

The invention provides a two-sided welding method for a U-shaped ribbed slab unit welding seam. The two-sided welding method comprises the following steps: cleaning the welding surface of a piece to be welded; placing a U-shaped rib on the surface of the piece to be welded, wherein an assembly groove is formed between the end part of a U-shaped ribbed web plate and the surface of the piece to be welded, and the groove angle is 50-60 degrees; carrying out positioning welding on the U-shaped rib and the piece to be welded in the horizontal position to obtain a U-shaped ribbed slab unit; welding a fillet welding seam at the jointing position of the inner side of the U-shaped ribbed web plate and the piece to be welded; and placing the U-shaped ribbed slab unit welded with the fillet welding seam on an anti-deformation slanting tension bed to carry out welding of an outer side welding seam, wherein a process of twin-wire submerged arc welding with single power supply is adopted. According to the two-sided welding method, a jointing welding seam between the U-shaped rib and the piece to be welded is changed into a two-sided fillet welding seam form from a single-sided fillet welding seam form in the prior art, so that stress amplitudes at a weld root and a weld toe are greatly lowered, the problem of initiation of fatigue cracks of the welding seam at the weld root is solved, and the fatigue performance at the weld toe is also improved.

Description

technical field [0001] The invention belongs to the manufacturing technology of steel structure bridges, and in particular relates to a double-sided welding method for U-rib unit welds. Background technique [0002] Steel box girders are generally composed of panel unit elements and floor unit elements. Orthotropic deck decks have the advantages of light weight and rapid construction, and are widely used in long-span bridges. All kinds of fatigue cracking problems of heterogeneous steel bridge decks are prominent, which has always troubled bridge builders. In the past few decades, researchers have gained a lot of experience and lessons, and carried out a lot of research work, aiming at improving and optimizing the welding details of orthotropic steel bridge deck, improving durability; but limited to the existing technology, U rib It can only be welded to the bridge deck from the outside. This kind of fillet weld is eccentric to the web of the rib. The bending stress of the ...

AI Technical Summary

Problems solved by technology

[0002] Steel box girders are generally composed of panel unit elements and floor unit elements. Orthotropic deck decks have the advantages of light weight and rapid construction, and are widely used in long-span bridges. All kinds of fatigue cracking problems of heterogeneous steel bridge decks are prominent, which has always troubled bridge builders

In the past few decades, researchers have gained a lot of experience and lessons, and carried out a lot of research work, aiming at improving and optimizing the welding details of orthotropic steel bridge deck, improving durability; but limited to the existing technology, U rib It can only be welded to the bridge deck from the outside. This kind of fillet weld is eccentric to the web of the rib. The bending stress of the wheel load acting on the root of the U-rib fillet weld through the bridge deck is too large. The existence of tensile stress increases the maximum effective tensile stress value at the tip of the incomplete weld root, so it is easy to produce fatigue cracks initiated from the root of the weld

In addition, the connection weld between the U rib and the unit element of the steel box girder bottom plate can only be welded from the outside, and the form of the weld is not reasonable

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