High-speed Railway of Jiangning Grand Bridge | China

Project Description

Jiangning Grand Bridge Steel Arch Structure Project

Nanjing–Ma’anshan High-Speed Railway, Jiangsu Province

The Jiangning Grand Bridge is a key control project on the Nanjing–Ma’anshan High-Speed Railway in Jiangsu Province. The bridge adopts a 128-meter-span inward-inclined basket-handle arch structure, characterized by its complex spatial geometry, high structural precision requirements, and advanced hybrid steel–concrete design.

The main arch ribs feature a dumbbell-shaped steel–concrete composite truss cross-section. Each arch rib consists of two Ø1200 mm steel pipes with a wall thickness of 18 mm, connected by a 16 mm thick gusset plate to form the dumbbell configuration. C55 non-shrink concrete is poured inside the steel pipes and gusset plates, creating an integral composite structural system with high load-bearing capacity and durability.

The two main arch ribs are inclined inward at an angle of 9° along the bridge axis, forming a spatial curved layout. At the arch foot, the clear spacing between the two ribs is 16.2 meters. Five horizontal bracing systems are installed between the arch ribs, including a single-line brace at the arch crown and K-shaped braces at other positions, ensuring overall stability and torsional stiffness.

The main arch ribs are connected to reinforced concrete tie beams through hangers. The upper ends of the hangers are anchored to the upper chords of the arch ribs, while the lower ends are anchored into the concrete beams, forming an efficient force transfer system.

All main steel components are fabricated using Q345qD steel plate, with a maximum weld thickness of 18 mm. The project demonstrates strong capabilities in complex arch steel structure fabrication, precision welding, and quality control for high-speed railway bridges, highlighting our expertise in large-span steel arch bridge manufacturing.

 

 

■ The main bridge is a 128 meter span inner inclined basket arch super large bridge, and the main arch rib section is dumbbell type concrete-filled steel tube truss.

■ The arch rib inclines to the center line of the bridge axis with an inclination of 9 °, which is a spatial curve. The distance between the centers of the two arch ribs at the arch foot is 16.2M, and the arch rib is 2 - φ 1200mm steel pipe with a wall thickness of 18mm.

■ Two steel pipes form a dumbbell shaped section, which is connected by battens. The thickness of battens is 16mm. C55 non-shrinkage concrete is poured into the main steel pipe and battens.

■ There are 5 transverse braces between the two main arch ribs, among which i-brace is set at the arch crown and k-brace is set for the rest.

■ The main arch rib is connected with the reinforced concrete beam through the suspender, the upper end of the suspender is anchored at the top chord of the arch rib, and the lower end is anchored at the concrete tie beam.

■ The main steel material is Q345qD plate, with the maximum welding thickness of 18mm. Adopt section hoisting technology and construct under the condition of continuous traffic of expressway.