On December 22, 2020, the world-class sea-crossing project, the Yongzhou Railway Advance Project, designed by the Fourth Railway Institute as the lead unit of the consortium, officially started construction.

Yongzhou Railway

The Ningbo-Zhou Railway starts from Ningbo East Station in the west, passes through Yinzhou District, Beilun District, Zhoushan City, Jintang Island, Cezi Island, Fuchi Island and Zhoushan Island. The design speed is 250 kilometers per hour. There are 7 stations on the whole line, of which Beilun West 4 stations, Jintang, Ma'ao, Zhoushan, and 3 existing stations in Ningbo East, Yunlong and Qiuai. The total length is 76.4 kilometers, of which the newly-built line is 70.1 kilometers long. The line is connected to the Ningbo-Taiwan-Wenzhou Railway to the south, to the Yongjin Railway to the southwest, to the Hangzhou-Ningbo Passenger Dedicated Line to the west and northwest, and connects to Hangzhou-Changzhou, Nanjing-Hangzhou, Shanghai-Hangzhou, Shanghe-Hangzhou lines through the Hangzhou hub. . The total investment of the project is about 27 billion yuan, and the construction period is 6 years.

According to the design, the Yongzhou Railway crossing the Jintang Waterway will adopt the tunnel scheme; the Xihoumen, Taoyaomen, and Fuchimen waterways will adopt the road-rail dual-purpose bridge scheme. By then, one tunnel and one bridge will both become the world's best. The construction of the Jintang Subsea Tunnel and the Xihoumen Bridge will be the key controlling major projects.

Jintang Subsea Tunnel

The 16.18-kilometer Jintang Submarine Tunnel is 10 kilometers longer than the tunnel of the Hong Kong-Zhuhai-Macao Bridge and is the world's longest submarine high-speed rail tunnel. The Hong Kong-Zhuhai-Macao Bridge cross-sea tunnel is 6.7 kilometers long and belongs to an immersed tube highway tunnel. The Jintang Tunnel is a high-speed rail shield tunnel. One-fifth of the entire line goes deep into the seabed, and it will realize the ultra-large diameter shield tunneling in the seabed and the large diameter shield A full-section secondary lining structure is set on the inner side of the tunnel segment, multiple waterproof systems are set on the outer side of the shield segment joints, and a longitudinal evacuation passage suitable for motor vehicles is set inside the railway shield tunnel.

Xihoumen Bridge

The Xihoumen Road-Rail Bridge with a main span of 1488 meters is a highway-rail joint bridge that spans the Xihoumen Waterway on the Yongzhou Railway and the Yongzhou Expressway double track. It adopts a cable-stayed and suspension cable combination system. After completion, it will become the world The highway-rail joint construction bridge with the largest upper span has increased the spanning capacity of Chinese railway bridges from kilometer level to 1,500 meters level.

In the design of the foundation of the main tower on the Jintang Island side, the design team of the Bridge Institute of the Fourth Railway Institute used circular caisson foundations. This foundation form is the first domestic cross-sea bridge adopted, and the side anchorage of Jintang Island is the first domestic use of rock anchors. The anchorage will greatly reduce the damage to the surrounding environment, reduce the construction period, and save project investment.

The Yongzhou Railway is a major project to realize the one-hour traffic circle of Zhejiang Province's high-speed railway. After completion, it will end the history of no trains in the Zhoushan Islands. It only takes 30 minutes from Ningbo to Zhoushan and 80 minutes from Hangzhou to Zhoushan. At the same time, the construction of this project will elevate the design level of Chinese bridges and tunnels to a new level of development. Editor/He Yuting