On December 10, the Shenshan Railway, designed by China Railway Siyuan Survey and Design Group (CRSD), officially began full-scale construction. Once completed, travel from the Shenshan Special Cooperation Zone to central Shenzhen will take only 30 minutes.

The Shenshan Railway is an important component of the coastal high-speed corridor among the "Eight Horizontal and Eight Vertical" main high-speed rail corridors in the National Medium- and Long-Term Railway Network Plan, and is a key project for improving the rail transit construction of the Guangdong-Hong Kong-Macao Greater Bay Area.

The line starts from Shenshan Station on the Guangzhou-Shanwei Railway, passes through the Shenshan Cooperation Zone and Huizhou City, and ends at Xili Station in the Shenzhen hub. It has a total length of 125.52 kilometers and a design speed of 350 kilometers per hour. A total of 6 stations are set along the line: Xili, Luohu North, Shenzhen Pingshan, Huizhou South, Huidong, and Shenshan. Among them, Xili, Luohu North, and Pingshan stations will also form comprehensive transportation hubs with multiple rail lines such as intercity railways and subways.

The entire line includes 18 new tunnels totaling 90.29 kilometers and 38 bridges totaling 25.979 kilometers, with a bridge-tunnel ratio of 92.63%. The total construction period is 5 years. The approved preliminary design budget estimate for the project is 48.79 billion yuan.

The Shenshan Railway is fully funded by Shenzhen, with Shenzhen Metro Group responsible for project implementation and asset management, and China Railway Guangzhou Group Co., Ltd. responsible for construction. As a locally funded high-speed railway, the Shenshan Railway has attracted much attention since the birth of the Bay Area plan.

■ The largest cluster of large-diameter shield tunnels

The Shenshan Railway runs through the urban areas of Shenzhen and Huizhou, where the economy is highly developed and pipe networks are densely distributed. The line crosses railways, rivers, expressways, urban roads, and sensitive ecological areas multiple times, making design and construction highly difficult.

The Shenshan Railway adopts 13.8-meter large-diameter shields, with 8 large-diameter shield machines constructing simultaneously. The large number of shield machines forms the largest large-diameter shield tunnel cluster in China. The tunnel runs parallel to the existing operating high-speed railway at close range for 43 kilometers. How to ensure the safe operation of the high-speed railway while achieving rapid and economical construction was full of challenges during the design stage.

During the design process, CRSD conducted special studies through multiple rounds of expert demonstration on construction parallel to existing lines, karst treatment in the shield tunnel section of the high-speed railway, and long-distance shield tunneling in hard rock strata, and adopted safe and reliable measures to ensure construction and operation safety.

■ The high-speed railway partial cable-stayed bridge with unequal-height towers and the largest span

The Shenshan Railway crosses the Shenzhen Reservoir, with the line adjacent to a Class I water source protection area on both sides. Together with the proposed Shawan River interception and drainage project and the planned expressway, it is arranged within a 100-meter-wide corridor. The construction environment is complex, placing higher requirements on design and construction.

The main bridge of the Shenzhen Reservoir Grand Bridge on the Shenshan Railway adopts a partial cable-stayed bridge with unequal-height towers. Its 242-meter main span crosses the reservoir in a single span, making it the largest-span partial cable-stayed bridge with unequal-height towers on a high-speed railway in China. The project integrates well with the surrounding environment and adjacent projects and will become a landmark building in the area after completion.

■ Connecting multiple transportation hubs

Building stations is building cities. Stations along the Shenshan Railway, including Xili, Luohu North, Pingshan, Huizhou South, and Shenshan, are all planned as comprehensive transportation hubs.

Xili Station

Xili Station will bring together 3 high-speed railways, 3 intercity railways, and 4 intercity rail transit lines, creating a new urban landmark in the western Qianhai central area.

Luohu North Station

Luohu North Station will connect the Shenshan Railway, 3 subway lines, and 2 medium-capacity transit lines. Surrounding roads will also be upgraded and reconstructed. It will become the transportation bridgehead for the northern gateway of Luohu District and accelerate the process of urban northward expansion.

Huizhou South Station

Huizhou City plans to extend Shenzhen Metro Line 14 to Huizhou South Station and build a new rail transit Line 1 to connect with the main urban area. Huizhou South Station will become a transportation hub connecting 2 high-speed railways, including Xiamen-Shenzhen and Shenshan, and 2 subways, supplemented by urban road traffic connections.

Shenshan Station

Shenshan Station is located in the Shenshan Cooperation Zone and is planned to connect 2 high-speed railways, including Guangzhou-Shanwei and Shenshan, 2 medium-capacity lines, 2 low-capacity lines, and various connection facilities, becoming the most important external comprehensive transportation hub of the Cooperation Zone.

In the future, departing from Shenzhen, the coastal high-speed railway will reach the eastern Guangdong city cluster in 1 hour, the West Coast city cluster in 2 hours, and the Yangtze River Delta city cluster in 5 hours. Travel time from Shenzhen to the Shenshan Cooperation Zone will be shortened from the current 47 minutes to 30 minutes.

As the main artery of the Shenzhen metropolitan area, the Shenshan Railway directly connects the central urban area of Shenzhen and the Shenshan Cooperation Zone, playing an important role in accelerating the construction of the coastal high-speed railway, optimizing the external railway corridors of the Shenzhen hub, and promoting the construction of the Shenshan Cooperation Zone.

Schematic diagram of winning bidders for the pre-station works of the Shenshan High-Speed Railway