In the bustling world of metro construction, the shift towards prefabricated components is gaining momentum, promising faster construction times and reduced environmental impact. However, the success of these prefabricated systems hinges on one critical factor: the connection methods used to assemble these components. A recent study, led by DING Xianli from the Guangzhou Metro Design and Research Institute, sheds light on this very issue, providing a comprehensive review of connection methods for prefabricated metro components, published in the journal ‘Chengshi guidao jiaotong yanjiu’ which translates to ‘Urban Rail Transit Research’.
The study, which systematically sorts through research progress in China and abroad, focuses on five mainstream connection methods: cast-in-place connection, steel grouting sleeve connection, bolted connection, welded connection, and steel component quick connection. Each method, according to the study, has its own set of strengths, weaknesses, and applicable scenarios.
DING Xianli and his team found that wet connection methods, such as cast-in-place and steel grouting sleeve connections, exhibit high load-bearing capacity and reliability. However, these methods come with longer construction cycles and relatively complex processes. “Cast-in-place connection is particularly sensitive to construction environment constraints, affecting efficiency,” DING Xianli notes. This sensitivity can lead to increased costs and delays, especially in complex urban environments.
On the other hand, dry connection methods like bolted connections, welded connections, and steel component quick connection eliminate the need for wet operations and offer relatively simpler construction. However, bolted connections are labor-intensive and have limited load-bearing capacity, while welded connections require high technical proficiency and are sensitive to working conditions.
The standout in the study is the steel component quick connection method. This method, with its advantages of fast construction, reliable quality, and strong load-bearing capacity, is particularly suitable for complex working conditions and space-constrained environments. This could be a game-changer for metro construction in dense urban areas, where space and time are at a premium.
The implications of this research are vast. As cities around the world continue to expand and metro systems become more prevalent, the demand for efficient and reliable connection methods will only increase. The findings of this study could shape future developments in the field, driving innovation and improving the overall efficiency and sustainability of metro construction.
For the energy sector, the shift towards prefabricated components and efficient connection methods could lead to significant energy savings. Faster construction times mean reduced energy consumption, while the use of prefabricated components can lead to less waste and more efficient use of materials. Moreover, the improved structural stability offered by these connection methods could lead to more durable and energy-efficient metro systems.
As we look to the future, the insights provided by DING Xianli and his team could pave the way for smarter, more efficient metro construction. By understanding the strengths and weaknesses of each connection method, engineers and designers can make more informed decisions, ultimately leading to better, more sustainable metro systems.