Impact Analysis of New Shield Tunnel Under-passing Construction on Existing Railways
Journal Title: Urban Mass Transit - Year 2024, Vol 27, Issue 12
Abstract
［Objective］ The construction of new shield tunnels under-passing existing railway can cause deformation of the former railway subgrade. To ensure the stability and safety of the existing railway, appropriate reinforcement measures must be adopted. ［Method］ The Shanghai Airport Connection Line under-passing Lijiatang-Shenzhuang Railway project is analyzed as a study case, which adopts a reinforcement scheme involving ′portal isolation piles+ground grouting′. Numerical simulation results and on-site monitoring data are used to assess the impact of shield tunnel under-passing construction on the existing railway, and to evaluate the effectiveness of the ′portal isolation piles+ground grouting′ reinforcement scheme. ［Result & Conclusion］ The shield tunnel under-passing construction may cause significant settlement of the existing railway subgrade, while the ′portal isolation piles+ground grouting′ reinforcement scheme effectively controls the above-mentioned railway subgrade deformation. According to numerical simulation results, the maximum settlement of existing railway subgrade decreases by 67% after reinforcement, and the convergence deformation on tunnel upper part decreases by approximately 41%. All deformations are within the limits specified by the relevant standards. On-site measurements confirm that the cumulative deformation of existing railway track and subgrade caused by the shield construction meets the regulatory requirements. However, due to the impact of shield tunneling, larger deformation fluctuations are observed in existing railway subgrade and track on one side of the shield tunneling.
Authors and Affiliations
Fei XIAO
Keywords
Related Articles
- EP ID EP752737
- DOI 10.16037/j.1007-869x.2024.12.032
- Views 22
- Downloads 0
Influence of Different Fiber Materials on the Performance of Concrete Segment Joints
［Objective］ Due to their low tensile strength and poor impact resistance, ordinary concrete segments are prone to problems such as cracking and deformation during the transportation and construction process. Adding fib...
Lightning Test and Simulation Research for Medium-speed Maglev Train
Objective When medium-speed maglev trains operate on elevated tracks, the carbody is susceptible to lightning strikes. If composite materials are adopted for medium-speed maglev train carbody, damage or even penetration...
Performance Evaluation of Rail Transit Station Land Use Based on Passenger Throughput-A Case Study of Shanghai
Objective Shanghai Master Plan (2017-2035) evaluates land use performance using the index of land use area for construction of GDP per unit area across the city. However, since rail transit stations are more concerned wi...
Simulation Analysis of Electromagnetic Interference Effects of AC Traction Metro Tunnels on Oil and Gas Pipelines
［Objective］ Currently, several cities in China are planning 25 kV AC (alternating current) power supply metro lines, inevitably there will be paralled sections of oillgas pipelines run parallel to metro tunnels. During...
Research on Metro Train Online Flexible Marshalling Technology Based on Wireless Communication
Objective In response to the national call of 'carbon peaking and carbon neutrality' polies, the metro industry urgently seeks to develop metro trains with the capability for rapid, efficient, and online dynamic flexible...