Hun River Extra Large Bridge on Shenyang-Baihe Railway

For the Shenyang‑Baihe Railway, steel structures are adopted for cross‑beams with single‑box ribbed sections. The box width is 3.2 m and box height is 3.5 m. The thickness of top and bottom plates is 36 mm, and web plates are 28 mm thick. Diaphragms are installed roughly every 2.0 m inside each steel cross‑beam. Support diaphragms are arranged at bearing locations, and vertical stiffeners are fitted between support diaphragms to resist bearing reactions and jacking reactions during bearing replacement. To achieve smooth stiffness transition and reasonable force transfer at the steel‑concrete composite segment on pier tops, the stiffeners of top and bottom plates transition into vertical force‑transfer end diaphragms. Force‑transfer diaphragms are set between end diaphragms and temporary‑support diaphragms. Shear studs are arranged on top plates, bottom plates and diaphragms within composite segments. Openings are cut on the bottom plate of steel cross‑beams in pier‑top zones. Main reinforcing bars of piers penetrate through bottom‑plate openings and extend upward to the top plates of steel cross‑beams. Construction is implemented by connecting pier reinforcing bars from inside the steel box downward through bottom‑plate openings. Piers adopt rectangular constant‑cross‑section structures with a transverse and longitudinal dimension of 3.0 m each.