Design and Implementation of a Rotating Bridge for Train, Ships, And Vehicle Transport at Same Elevation

In low lying coastal zones and crowded urban corridors, railway lines, roads, and navigable waterways often compete for space, creating complex infrastructure bottlenecks. Conventional fixed bridges with high clearance demand long approach ramps that conflict with strict railway grade restrictions. Building separate structures for each mode escalates both land use and financial costs. This work proposes a rotating (swing) bridge that accommodates trains, ships, and road vehicles on the same level without any gradient. The structure uses a rim bearing slewing system to rotate a steel truss deck by 90°, allowing ships to pass without vertical obstruction while preserving a flat surface for rail and road traffic. Finite element simulations confirm that the cantilever deflection when the bridge is open stays within L/400. A programmable logic controller (PLC) combined with laser guided positioning yields a rail alignment accuracy of ±1.5 mm, exceeding the required safety margin. The entire opening closing cycle takes less than six minutes, demonstrating practical operability. Compared to a traditional high level bridge, this design reduces steel consumption by about 30% and avoids lengthy approach embankments, making it a cost effective, space saving option for modern multimodal hubs. The results also offer a reference for future smart movable bridges that incorporate artificial intelligence for predictive maintenance and sustainable materials.