On August 13, the bottom slab of the west-side launching shaft foundation pit of the Yangzhou East Railway Station comprehensive transportation hub integration construction project for the Shanghai-Chongqing-Chengdu (North Yangtze River) High-Speed Railway — the municipal pre-embedded works — was successfully closed, marking the successful completion of bottom sealing for the deepest foundation pit currently under construction in Yangzhou, and laying a solid foundation for subsequent main structure concrete pouring and section tunnel boring.

This project is the third phase of the municipal pre-embedded works, continuing from the completed Phase I and Phase II, and is an important prerequisite project for ensuring the region's subsequent planned development.The foundation pit excavation depth reaches 33.864 meters, making it the deepest foundation pit currently under construction in Yangzhou. Construction faces multiple challenges: the pit is located in multi-layer fully sandy permeable strata, with abundant regional groundwater reserves and complex hydrogeological conditions; the surrounding construction environment is extremely sensitive, with the west side only 30.14 meters from the Liaojia Gou Taiping River embankment and the east side only 0.56 meters from the underground supporting parking garage under construction. In addition, the project's foundation pit safety and environmental protection levels are both Grade I standards, imposing high safety and environmental control requirements.

In response to potential construction risks in this ultra-deep foundation pit, such as water inrush, deformation, and disturbance of surrounding strata, the Transportation Construction Management Company coordinated all participating units and, strictly in accordance with the special construction plan, systematically established a comprehensive, three-dimensional safety control technical system.

First,a triple three-dimensional seepage-control structure was created using ultra-deep diaphragm walls combined with wall-joint water sealing and base water-blocking reinforcement technology.

Second,six levels of concrete struts and two levels of steel struts were installed to form composite layered support, and dynamic stress adjustment technology was introduced to effectively control foundation pit deformation and enhance overall stability.

Third,based on the site's hydrogeological characteristics, dewatering and recharge well groups were arranged by zone, and 24-hour sensor monitoring data were used to dynamically regulate pumping and recharge volumes, minimizing the impact of construction on surrounding river embankments and projects under construction. The project also established a full-coverage informatized monitoring network to collect key parameters such as diaphragm wall displacement and strut axial forces in real time, and set up a rapid early-warning and response mechanism, comprehensively fortifying the defense lines for construction safety and the surrounding environment through digital and refined technical means.

Next, the Transportation Construction Management Company will advance the hub supporting projects to high standards, improve the interconnectivity functions of Yangzhou East Station, and inject strong momentum into Yangzhou's efforts to build a comprehensive transportation network with strong external links and smooth internal connections.

Source: Yangzhou Traffic Radio