In the heart of China’s bustling urban expansion, a critical challenge has emerged: how to efficiently and safely integrate new metro stations into long intervals within loess strata, a type of soil known for its unique geological properties. This conundrum has been tackled head-on by ZHOU Dingheng, a leading expert from the China Railway Fifth Survey and Design Institute Group Co., Ltd. in Beijing, whose groundbreaking research has been published in the esteemed journal ‘Chengshi guidao jiaotong yanjiu’ (Urban Rail Transit Research).
ZHOU Dingheng’s study focuses on the interval between Hangtiancheng Station and Dongchang’anjie Station on Xi’an Metro Line 15, a region characterized by long metro intervals and loess strata. The research meticulously analyzes the influencing factors related to adding a new station in such a context, optimizing and comparing both horizontal and vertical alignments.
The study delves into eight construction methods, including open excavation, mined tunneling, and various combinations thereof. Two schemes stand out: a three-level underground station using the full PBA (pile-beam-arch) method and a combined method of open excavation for the first and second underground levels with CRD (cross diaphragm method) for the third level.
“When constructing PBA method deep-buried stations, the foundation bearing capacity is often insufficient,” ZHOU Dingheng explains. This insight underscores the necessity for innovative solutions in metro construction, particularly in challenging geological conditions.
The research also conducts a 3D time-history analysis under E3 seismic loading, revealing that while the structural deformation rate of deep-buried stations with separate concourse and platform structures remains within allowable limits, certain local areas exhibit low safety margins. This finding highlights the importance of structural reinforcement measures in ensuring the safety and longevity of metro infrastructure.
The implications of this research are profound for the construction and energy sectors. As urbanization continues to accelerate, the need for efficient and safe public transportation systems becomes ever more critical. ZHOU Dingheng’s work provides a robust framework for optimizing track-station alignment and construction methods, ensuring that new metro stations can be seamlessly integrated into existing networks without compromising safety or economic efficiency.
Moreover, the study’s focus on loess strata offers valuable insights for construction projects in similar geological conditions, paving the way for more resilient and sustainable urban development. By addressing the challenges of long metro intervals and loess strata, ZHOU Dingheng’s research not only shapes the future of metro construction but also contributes to the broader goal of creating smarter, more sustainable cities.
As the world grapples with the complexities of urban expansion, studies like ZHOU Dingheng’s serve as a beacon of innovation and practicality, guiding the way towards a future where infrastructure and technology harmoniously coexist.