In the bustling world of urban infrastructure, the integrity of underground stations is paramount, especially when it comes to waterproofing. These subterranean hubs, often nestled in soil and rock layers, face relentless groundwater erosion and pressure infiltration. A breach in waterproofing can lead to more than just inconvenient leaks; it can compromise passenger safety, degrade operational quality, and jeopardize the longevity of concrete structures. Enter ZHU Jun, a researcher from Wuxi Metro Group Co., Ltd., who has been delving into the intricacies of waterproofing technologies for underground stations with assembled superposed structures (AS stations).
ZHU Jun’s recent study, published in ‘Chengshi guidao jiaotong yanjiu’ (Urban Rail Transit Research), focuses on the Nanmen Station of the Wuxi-Jiangyin Intercity Rail Transit Project. The research introduces an integrated ‘three-in-one’ waterproofing system designed to fortify AS stations against the relentless onslaught of groundwater. “The key to effective waterproofing lies in understanding the unique challenges posed by the bonding surfaces between new and old concrete,” ZHU Jun explains. “These surfaces are subject to both tensile and shear forces, each requiring a tailored approach.”
The study delves into two critical technologies: the treatment of bonding surfaces and the use of micro-expansion, low-shrinkage, crack-resistant concrete. For bonding surfaces primarily under tensile forces, the research advocates for the water-washed aggregate exposure construction technique. This method ensures a robust bond, minimizing the risk of water infiltration. Conversely, for surfaces under shear forces, the roughened surface construction technique is recommended. This approach enhances the surface’s ability to withstand lateral stresses, further bolstering the structure’s integrity.
But the innovations don’t stop at surface treatments. ZHU Jun’s team also explored the use of lightweight sand internal curing agents and expansive agents in concrete mixtures. The results were striking: the concrete exhibited exceptional low-shrinkage and crack-resistant properties. This breakthrough could revolutionize the way underground stations are constructed, offering a more durable and reliable solution to waterproofing challenges.
The implications of this research extend far beyond the immediate benefits to the construction industry. For the energy sector, which often relies on underground infrastructure for power distribution and storage, these advancements could mean more resilient and efficient systems. Reduced maintenance costs and extended service life of concrete structures could lead to significant savings and improved operational reliability.
As urbanization continues to accelerate, the demand for robust and efficient underground infrastructure will only grow. ZHU Jun’s work provides a roadmap for future developments in this field, offering a glimpse into a future where underground stations are not just functional but also resilient and sustainable. The integration of these advanced waterproofing technologies could set a new standard for underground construction, ensuring that our cities remain safe, efficient, and prepared for the challenges of tomorrow.