On January 8, as the final bucket of concrete was precisely poured into place, the main structure of Foundation Pit No. 2 in the western section of Bid Section 4 of the Shenzhen-Jiangmen Railway, constructed by China Railway Sixth Group, was successfully topped out. This marks the successful completion of a controlling project and high-risk node along the entire line, bringing the project into a new phase and laying a solid foundation for the subsequent safe and efficient tunneling.

     The topped-out Foundation Pit No. 2 is located near Shenzhen Bao'an International Airport, where construction conditions are extremely complex, and it is massive in scale and highly technically demanding. The pit is 285 meters long, over 51 meters wide at its widest point, and 26.64 meters deep at excavation, resembling a carefully constructed "underground maze," with a total concrete pour volume of 1,570 cubic meters. Its construction safety, quality, and progress are directly tied to the advancement of the entire Shenzhen-Jiangmen Railway project.

      Faced with the sensitive environment adjacent to the airport, complex geological conditions, and numerous constraints of construction in a dense urban area, the project team deeply integrated technological innovation with refined management. They fully applied BIM technology for whole-process simulation and optimization and introduced an intelligent monitoring system, effectively installing a "sky eye" over the foundation pit to achieve real-time sensing and early warning of support structure deformation and surrounding environment stability. Through a series of measures such as dynamically optimizing the support scheme and scientifically implementing zoned flow-line construction, the team successfully resolved multiple risk challenges, ensuring that this mega foundation pit safely and steadily "grew" to its topping-out under complex conditions.

      The Shenzhen-Jiangmen Railway is an important component of the coastal corridor in the national "Eight Vertical and Eight Horizontal" high-speed railway network. The completion of the main structure of Foundation Pit No. 2 not only clears key obstacles and provides an irreplaceable working face for subsequent tunnel construction within the bid section, but also means that the "throat" of the underground section of this major transportation artery connecting the east and west banks of the Pearl River Estuary has been initially opened.

      Once completed, the project will efficiently connect core cities of the Guangdong-Hong Kong-Macao Greater Bay Area, including Shenzhen, Dongguan, Guangzhou, Zhongshan, and Jiangmen, and achieve a half-hour direct trip from Guangzhou Nansha to Shenzhen Qianhai. It is of vital strategic significance for improving the comprehensive transportation network layout of the Greater Bay Area, accelerating the realization of the "Greater Bay Area on Rails" blueprint, and promoting deep integration and coordinated development of the regional economy and society.