Innovative engineering solutions for the crossing strait tunnel

This perspective article examines the crossing strait tunnel (CST) as a sophisticated and integrated system, in which safety, construction efficiency, and energy sustainability represent interconnected priorities for next-generation projects. In response, this paper identifies and proposes key technologies necessary to advance long CST development. Analysis of global cases reveals a predominant trend towards significantly larger cross-sections in this century compared to the mid-1900s. Accordingly, the paper proposes integrated evacuation frameworks for both cross-sectional and longitudinal layouts, incorporating energy balance considerations to enhance overall operational safety and efficiency. To achieve rapid tunneling in challenging marine environments, the concept of an offshore floating platform (OFP) is introduced as a foundation for deepwater construction. The OFP is designed to serve as a hub for the concurrent launch and operation of multiple tunnel boring machines (TBMs), integrating robotic systems, autonomous controls, and advanced information technology (e.g., real-time monitoring) to enable efficient tunneling advancement. Furthermore, the OFP's role in achieving energy and ecological balance is conceptualized. Collectively, these proposed solutions aim to address the unique challenges of long CSTs and stimulate discussion on sustainable and efficient tunnel development.