In the bustling world of urban infrastructure, the construction of interchange hubs for high-speed railways and metros presents a unique set of challenges, particularly when it comes to post-construction foundation pit design. A recent study led by SUN Bo from China Railway Siyuan Survey and Design Group Co, Ltd, Wuhan, China, delves into these complexities, offering insights that could revolutionize how we approach such projects. The study, published in ‘Chengshi guidao jiaotong yanjiu’ (Urban Rail Transit Research), highlights the technical hurdles and environmental sensitivities that arise during the excavation of foundation pits in interchange hub areas.
The research focuses on a high-speed railway and metro interchange hub project situated in deep silty soil layers. The study emphasizes the need for a meticulous design plan that considers the surrounding environment, the layout of individual buildings, and excavation depth. SUN Bo and his team employed finite element software to simulate the entire construction process in 3D, evaluating the potential impact on existing structures. The results were then cross-verified with on-site monitoring data, ensuring the design’s feasibility and effectiveness.
One of the standout findings is the exceptional performance of the TRD (trench-cutting re-mixing deep wall method) combined with an inserted steel bracing system. This method proved to be highly effective in water retention, making it ideal for projects with moderate depth, thick permeable layers, and stringent water retention requirements. “The TRD+inserted steel bracing system performs excellently in water retention,” SUN Bo noted, “and is suitable for foundation pit projects with moderate depth, thick permeable layers, complex surrounding environments, and stringent water retention requirements, where the water curtain must extend to the impermeable layer.”
The study also underscores the importance of integrating subsequent foundation pit construction into the protection scope of previously constructed buildings. By adopting a co-construction plan and prioritizing scientific segmentation and excavation sequencing, the adverse impact on existing structures can be significantly mitigated. This approach not only enhances safety but also optimizes resource allocation, reducing temporary engineering work and maximizing the interests of all parties involved.
The implications of this research are far-reaching, particularly for the energy sector. As urbanization continues to accelerate, the demand for efficient and sustainable infrastructure solutions will only grow. By providing a comprehensive framework for post-construction foundation pit design, this study offers a blueprint for future developments in the field. It encourages a more holistic approach to construction, one that considers environmental impact, structural integrity, and economic viability.
As we look to the future, the insights gained from this research could shape the way we build our cities. By embracing innovative technologies and methodologies, we can create more resilient and sustainable infrastructure that meets the demands of a rapidly evolving world. The findings published in ‘Urban Rail Transit Research’ serve as a testament to the power of scientific inquiry and its potential to transform the construction industry.