Study on Stability of Small Clearance Shield Tunnel Excavation Face
Journal Title: Urban Mass Transit - Year 2025, Vol 28, Issue 1
Abstract
［Objective］ Determine the limit support pressure required to maintain tunnel face stability during the construction of double-line small clearance shield tunnel. ［Method］ The excavation stability of double-line small clearance shield tunnel is studied by using a combination of numerical simulation, theoretical analysis and engineering verification. Numerical simulation is used to analyze the instability mode and limiting support pressure of double-line small clearance shield tunnel face. Based on the numerical simulation results, an analytical model for the instability of a double-line shield tunnel excavation face is proposed, and the limit support pressure required to maintain the tunnel face stability is derived by using the limit equilibrium theory. ［Result & Conclusion］ During the construction process of the small-clearance shield tunnel, a combined soil arch will be formed. Under the action of the combined soil arch, the limit support pressure required to maintain the stability of the double-line small-clearance tunnel excavation surface will increase significantly. Theoretical analysis shows that when the clearance is less than 0.5 D (D is the tunnel diameter), the limit support pressure increases with the increase of the clearance; when the clearance exceeds 0.5D, the limit support pressure decreases with the increase of the clearance; when the clearance exceeds 2.0D, the combined soil arch cannot be formed, and the failure mode in this case is the same as that of the single-hole tunnel, and the clearance no longer affects the limit support pressure.
Authors and Affiliations
Qi GAO
Keywords
Related Articles
- EP ID EP754995
- DOI 10.16037/j.1007-869x.2025.01.018
- Views 33
- Downloads 0
Safe Distances between High-Speed Railway 10 kV/0.4 kV Indoor Substations and Signal Rooms
［Objective］ When railway 10 kV/0.4 kV indoor substations and signal rooms are constructed at the same location, electrical equipment and signal equipment arranged too far apart will waste land resources, while placing...
Mechanical Behavior of Urban Rail Transit Station Structure Based on Existing Shield Tunnel Interval Underground Excavation Construction
Objective Cancer Hospital Station on Shenzhen Rail Transit Line 14 adopts a scheme of large-diameter (8.5 m) shield tunnel expansion featuring tunnel-first and station-later. During the connection of the main station str...
Research on Track-covering Vacuum Cleaner with Adjustable Parameters for Urban Rail Transit
[Objective] In view of the difficulty to remove the iron dust generated by rail grinding in urban rail transit, it is necessary to design a set of track-covering vacuum cleaners with adjustable parameters (abbreviated as...
Failure Fault Analysis and Improvement Recommendations for Axlebox Bearing Failures in Metro Vehicle
［Objective］ Axlebox bearing failures in metro vehicles can lead to wheelset seizing, resulting in scenarios ranging from passenger evacuation and vehicle rescue to severe incidents such as interval blockages or even de...
Design and Research of Vehicle-end Turning Hydraulic Device for Modern ART Tram
［Objective］ Modern ART (autonomous rail transit) trams often adopt multi-car articulated configurations in operation, because articulation joints possess significant degrees of freedom, relating the smooth operation of...