Study on ground settlement and structural deformation for large span subway station using a new pre-supporting...

Area of Science:

• Civil Engineering
• Geotechnical Engineering
• Construction Engineering

Background:

• Excavation of large underground spaces, especially subway stations, presents challenges in shallow depths and soft soil conditions.
• Traditional methods often struggle to adequately control ground settlement and ensure structural stability.
• The need for advanced pre-supporting systems is critical for safe and efficient underground construction.

Purpose of the Study:

• To introduce and evaluate a novel Steel Tube Slab (STS) system for shallow underground space excavation.
• To assess the effectiveness of the STS method in controlling ground settlement and structural deformation.
• To investigate the application of the STS system in the construction of ultra-shallow, large-span subway stations.

Main Methods:

• Development and implementation of the Steel Tube Slab (STS) system, connecting steel pipes with flanges, bolts, and concrete.
• On-site monitoring of ground settlement and structural deformation during subway station construction.
• Establishment and validation of a numerical model using monitored data for further analysis.

Main Results:

• The STS system demonstrated effective flexural capacity and lateral stiffness.
• Monitoring data confirmed significant control and reduction in ground settlement compared to traditional methods.
• Numerical model validation showed good agreement with monitored results, confirming the system's reliability.

Conclusions:

• The Steel Tube Slab (STS) system is a viable and effective pre-supporting solution for shallow, large-span underground excavations.
• The STS method significantly mitigates ground settlement, proving advantageous for construction in soft soil environments.
• This system offers a promising alternative for complex underground engineering projects, enhancing safety and minimizing environmental impact.