Deformation and Dynamic Response Analysis of Metro Shield Tunnel Under-Crossing Existing Railway Frame Bridge
Journal Title: Urban Mass Transit - Year 2025, Vol 28, Issue 4
Abstract
［Objective］ At present, there are few studies on the interaction between the under-crossing shield and the upper vehicle-track structure. In order to ensure the safety of new metro shield construction and existing line operation, it is necessary to analyze the influence law of metro shield construction disturbance and train load on the deformation characteristics and dynamic response of the existing structure. ［Method］ Based on the Changsha Metro Line 6 shield tunnel project under-crossing the existing Beijing-Guangzhou Railway frame bridge , an excavation submodel of the shield tunnel under-crossing railway frame bridge and a vehicle-track dynamic coupling submodel are established. Numerical software is adopted for joint simulation to study the deformation of strata, frame bridge and track structure under different working conditions such as shield excavation process, grouting pressure, soil chamber pressure, stratum reinforcement, train speed, etc., so as to summarize the changing laws of vehicle-track dynamic response. ［Result & Conclusion］ The maximum settlement caused by advancing excavation of the shield left line is about 3.0 mm. After the excavation of the right line, the maximum settlement occurs at the position offset towards the center of the left and right lines, and the maximum settlement value reaches 5.4 mm. The track settlement caused by the advancing shield tunnel is slightly greater than the settlement caused by the following excavation; the car body vibration acceleration and the wheel-rail force increase when the train speeds up, and the wheel-rail vertical force is more affected by the train speed than by the wheel-rail lateral force; the vibration displacement, the car body vibration acceleration, the wheel-rail force and the derailment coefficient all gradually increase with the continuous advancement of the shield excavation, but not by much; after increasing grouting pressure, soil chamber pressure and taking ground reinforcement measures, the vertical rail vibration displacement is reduced by 14.7%, 11.5% and 44.1% respectively compared with the excavation without taking measures. During the shield construction process, ground reinforcement measures should be taken for the smooth shield tunnel construction and normal railway operation.
Authors and Affiliations
Xinhui TANG, Xiangen LAI, Weizheng LIU, Shide LU, Xibing LU
Keywords
Related Articles
- EP ID EP766631
- DOI 10.16037/j.1007-869x.2025.04.024
- Views 10
- Downloads 0
Influence of Different Opening Positions of Shield Method Connecting Passage on Main Tunnel Segment Internal Force
Objective In the 9 m level large-diameter shield tunneling, there are no engineering cases using shield method for constructing connecting passages yet. Due to the influence of clearance and evacuation platform height, a...
Research and Application of Urban Rail Transit Train Collision Performance
［Objective］ In order to effectively reduce the hazards from the collision of urban rail transit trains and thereby improve the safety of train operation, it is necessary to conduct research on the collision performance...
Connotation and Model Analysis of Rail Transit Interconnection and Interoperability under Multi-Network Integration Background
[Objective] At present, the regional rail transit system in China has entered a new stage of multi-network integrated development, and its operation and management also presents new characteristics of multi-level, multi-...
Analysis of Bearing-settlement Characteristics of Extra-long Bored Piles in URT Deep Soft Stratum Underground Station
Objective To effectively control the deformation of station structure during the excavation and usage of deep foundation pit in soft soil stratum, and to increase the bearing capacity of foundation pit bottom, it is nece...
Research on Circumferential Deformation of Metro Shield Tunnel Based on FBG Monitoring Technology
Objective FBG (fiber bragg grating) monitoring technology features fast dynamic response, strong anti-interference, high precision and strong durability, and can realize long-distance real-time monitoring. The feedback c...