1. Project Overview

The Bayou Bridge is the main urban road of Ningbo City. It is located on the east side of the Sanjiangkou of Yaojiang Bay (see Figure 1). The main bridge is a continuous steel truss arch bridge with a span of 48m+180m+48m=276m. The main bridge is 43.6m wide. The main bridge three-span continuous steel truss arch bridge, the main bridge arch rib is composed of two trusses and six wind braces, the lateral center spacing of the two arch ribs is 33.6m, and the vertical center spacing of the upper and lower chords is 4.5m at the vault. The lower chord adopts a quadratic parabola with a vector height of 36m and a span ratio of 1/5. The upper chord is combined with a quadratic parabola and a circular curve. The main structural steel material is Q370qE and Q345qD steel, and the total bridge steel capacity is about 7700t.

Figure 1 Wantou Bridge Real Scene

2. Process difficulties

The difficulty of the project is that the steel arch rib box type edge fittings and the steel main beam angular welds are all fully welded. According to the needs of different positions, the corresponding partitions of the arch ribs and the rib cages are all made of thick plate full penetration welding. How to ensure the welding quality of the penetration welds is such a large number of penetration welds. The key to the manufacture of bridge steel structure.

3. Welding joint qualification standards

The welded joint and weld yield strength, tensile strength, elongation after fracture and joint V-type low-temperature impact absorption energy are not lower than the standard value of the parent metal (see Table 1); the highest hardness HV10 of the welded joint three zones is not higher than 350HV; The butt joint is cold-bent 180° without cracking.

For more information, please refer to the attachment or read the 18th issue of Metalworking (Hot Processing).

Load Cells By Structural