Abstract:The Shenzhen–Zhongshan Link (Shenzhong Link) is the world's first integrated cross-sea cluster project featuring a "bridge-island?tunnel-undersea interchange", and it is a key national project. The main structures include a 17-kilometer-long sea-crossing bridge and a 6.8-kilometer-long submarine tunnel. The project officially opened to traffic on June 30, 2024, with an average daily traffic volume of approximately 90,000 vehicles. Owing to the alternating loads from vehicles as well as wind, waves, and currents, fatigue issues are prominent. Moreover, the structures are exposed long-term to a marine environment characterized by high temperature, high humidity, and high salinity (fog), leading to severe corrosion problems. Considering that both corrosion and fatigue, as well as their coupled effects, significantly impact structural durability, this paper conducts research on key technologies for ensuring the durability of the Shenzhen–Zhongshan Cross-Sea Bridge, with a particular focus on marine concrete, steel beams, and main cables.