Risks and Countermeasures for the Shenzhen-Guangzhou-Zhongshan (SGZ) Shield-Tunnel Project Crossing the Pearl River Estuary

Regarding the risks involved in the construction of a long and deep submarine tunnel, such as complex geology, environmental protection, port industry, waterway transportation, air transportation, and abnormal meteorology, the environmentally friendly shield-driven tunnel construction method option has unique advantages. Based on the construction characteristics of the Shenzhen-Guangzhou-Zhongshan (SGZ) fixed link that crosses the Pearl River estuary, the achievements of the Guangzhou Metro in similar mixed ground, as well as the construction experience gained from international large-diameter, high-hydraulic-pressure and long-distance shield tunnel projects, the following conclusion is derived in this paper: the three-tube tunnel system is the optimal construction scheme because of its suitable functions, guaranteed quality, reasonable costs, and controllable risks. Additionally, a further analysis of the risks and countermeasures is described as a reference for similar projects.