The Guangzhou-Zhanjiang Bay high-speed railway undersea tunnel will soon cross the sea

The longest undersea tunnel in China -- Zhanjiang Bay Undersea Tunnel of Guangzhou-Zhanjiang High-speed Railway ushered in an important node! On May 8, "Yongxing" shield tunneling machine finished the factory manufacturing in Jiangmen, and will be shipped to the Guangzhou-Zhanjiang Bay high-speed railway submarine tunnel for assembly and use.

The Guangzhou-Zhanjiang high-speed railway line leads out of Guangzhou Railway Station, and 9 new stations are set up: Foshan Station, Pearl River Delta Airport Station, Xinxing South Station, Yangchun East Station, Yangjiang North Station, Mata Station, Maoming South Station, Wuchuan Station and Zhanjiang North Station. The new line is 401 km, with a design speed of 350 km/h, and the construction period is 5 years.

Zhanjiang Bay undersea tunnel is a key control project of Guangzhou-Zhanjiang high-speed railway. The new central station of this new line -- Zhanjiang North Station, is located in the downtown area of Zhanjiang, which will realize the "high-speed railway into the city" and greatly facilitate the transportation of the people. Using tunnel to cross the sea can effectively retain the existing urban skyline of Zhanjiang Bay and minimize the impact on urban landscape, which can not only avoid the impact of the project on the Marine ecological environment, but also not affect the passage of the waterway.

Shield tunneling machine from the initial well, mainly through the silty clay and sand. The line passes through Dongwang Avenue, Dongcheng West Road and Zhanjiang Olympic Sports Center successively. The line crosses Longwangwan Road into the sea area and runs parallel with Zhanjiang Bay Bridge. After leaving Zhanjiang Bay in the Sino-Australian Friendship Garden in Haixi, the line crosses Leshan Road, the main road of Zhanjiang City with dense structures on both sides. Due to poor geological conditions, large excavation diameter, long tunneling distance and dense underground pipe network, the construction is difficult, and the requirements for operation, parameter control and equipment performance of shield tunneling machine are very strict.

For this project the characteristics of the shield machine long distance alone head driving, "yongxing date" of shield machine cutter using atmospheric pressure cutter disc, in order to adapt in silty clay formation efficient tunneling, selection of the shield larger than the average 45% cutter opening ratio, at the same time, in view of the shield machine cutter easy construction difficulties of mud cake, optimize the flushing system to strengthen the center, Prevent the accumulation of muck in the center area of cutter head and the bottom of excavation chamber. The slag outlet under the air cushion chamber is equipped with the device of "stirrer + roller crusher", which is used for the first time in China, to break the block clay cut off by the cutter head more effectively, which is conducive to the removal of slag and improve the circulation slag discharge efficiency.

Western Guangdong is accelerating its integration into the interconnected development of the Guangdong-Hong Kong-Macao Greater Bay Area. As the high-speed rail project with the longest construction mileage and the largest investment in Guangdong, Guangzhou-Zhanjiang high-speed railway is a strong support for building a new regional development pattern of "One Core, One Belt, One Region".