On the afternoon of April 12, aboard the drilling vessel “Rongyang 288”, as the last drilling casing was retrieved from the undulating sea, the offshore exploration work for the Hangzhou Bay Sea-Crossing Bridge of the Nantong-Suzhou-Jiaxing-Ningbo Railway, for which China Railway Design Corporation (CRDC) is responsible for overall design, was successfully completed, laying a solid foundation for the project's preliminary design work. The Hangzhou Bay Sea-Crossing Bridge is 29.2 kilometers long and designed for a speed of 350 kilometers per hour. Once completed, it will become the world's longest high-speed railway sea-crossing bridge with the highest construction standards.

　　According to Zhang Peng, head of the geological specialty at CRDC: “The offshore exploration for the Hangzhou Bay Sea-Crossing Bridge lasted five months, completing two and a half months ahead of schedule. The sea has strong winds and high waves, rapid tides and currents, and poor seabed stability. Offshore survey work involves great risks and challenges and is extremely difficult.”

　　To overcome the difficulties and low success rate of conventional offshore drilling methods, the geological exploration team, after multiple field explorations and technical demonstrations, innovatively developed a needle-shaped hard alloy rib-type follow-up pipe drilling technique, increasing the success rate of a single drilling operation from 60% to over 90%.


　　Zhang Jian, chief engineer of the Nantong-Suzhou-Jiaxing-Ningbo Railway project at CRDC, introduced that the Hangzhou Bay Sea-Crossing Bridge is designed with ballastless track and includes three navigation channel bridges (north, middle, and south) and approach bridges in the sea, shallow water, and shoal areas. It is an ultra-long high-speed railway bridge cluster project that will set multiple world records and is of milestone significance to the world's railway bridge and even bridge engineering fields.

　　The north navigation channel bridge has a main span of 450 meters and adopts a concrete box-steel truss composite cable-stayed bridge with ballastless track, which is the first use in the world's high-speed railway construction. The sea approach bridge uses 80-meter main span prestressed concrete continuous beams, with a maximum continuous length of 3,080 meters, setting a world record for ultra-long continuous, large-span, curved continuous beam seamless tracks.

　　“In the design of the Hangzhou Bay Sea-Crossing Bridge, we also carried out research and design for the entire life cycle of multiple systems, including evacuation and rescue, operation and maintenance, and four-electricity integration for ultra-long railway sea-crossing bridges, accumulating engineering experience for subsequent sea-crossing railway projects,” said Zhang Jian.


　　The Nantong-Suzhou-Jiaxing-Ningbo Railway is part of the coastal corridor of the medium- and long-term railway network plan, with a design speed of 350 kilometers per hour. The project starts from Nantong West Station in Nantong City, crosses the Yangtze River, passes through Suzhou City and Jiaxing City, crosses Hangzhou Bay, and enters the Ningbo hub via Cixi City. The total operating length of the main line is 310 kilometers, with 10 stations: Nantong West, Zhangjiagang, Changshu West, Suzhou North, Fenhu, Jiaxing North, Jiaxing South, Haiyan West, Cixi, and Zhuangqiao.

　　Once completed, the Nantong-Suzhou-Jiaxing-Ningbo Railway will accelerate the improvement of the Yangtze River Delta rail transit network system, greatly shorten the travel time and distance between Ningbo and Shanghai, Suzhou, Beijing, and other places, further guide regional coordinated development, become a new engine for the development of the Yangtze River Delta region, and inject strong momentum into the development of the Yangtze River Economic Belt and the integrated development of the Yangtze River Delta region.