Overall Design of Hangzhou Bay Sea-Crossing Railway Bridge

Carrying a section of the Nantong-Suzhou-Jiaxing-Ningbo High-speed Railway, the total 29. 2 km-long Hangzhou Bay Sea-Crossing Bridge are paved with ballastless tracks and allows trains to travel at a maximum speed of 350 km/h. The Bridge consists of the north, central and south navigable bridges, as well as an offshore approach and a shoal area approach. The north navigable bridge is a two-pylon cable-stayed bridge with spans ( 71. 85 + 1 69. 5 + 450 + 1 69. 5 + 71. 85) m, the superstructure consists of steel box girders and steel trusses, and the stay cables are fanned out in double cable planes. The central navigable bridge is a three-pylon steel truss girder cable-stayed bridge with spans (85. 4 + 182 + 2 X 448 + 182 + 85. 4) m, the stay cables are arranged in double cable planes, the central pylon is fixed with the deck, while the two side pylons are elastically constrained, which improves the stiffness and economy of the bridge, and is more favorable for the track regularity. The south navigable bridge is a two-pylon steel truss girder cable-stayed bridge with spans (71. 25 + 1 54 + 364 + 1 54 + 71. 25 ) m, the stay cables are arranged in double cable planes. The offshore approach is a prestressed concrete (PC) bridge consisting of long continuous units with 80 m-long spans, multiple piers are fixed with the deck, and seismic mitigation and isolation system is used to minimize the scope of the foundation and reduce girder-end displacements; the approach features a 60 m-long simply-supported span bet-ween the first and second continuous units, aiming to accommodate the thermal effect on the structure and scale down the track expansion and contraction tuners. The shoal area approach is a simply-supported PC bridge containing multiple spans of 48 and 40 m. The durability of the concrete and steel structures in the marine environments is specially designed and additional measures are taken to improve the durability. The bridge is a typical precast segmental construction project, where the main girders of the navigable and approach bridges are all precast components, and the foundations of the offshore approach are composed of driven steel pipe piles. © 2023 Wuhan Bridge Research Institute. All rights reserved.