Deformation Effect Analysis of Shield Tunnel Closely Side-passing Viaduct Pile Foundation
Journal Title: Urban Mass Transit - Year 2024, Vol 27, Issue 9
Abstract
Objective Shield tunneling may cause displacement and deformation of the nearby viaduct foundation and reduce its bearing capacity. Therefore, the deformation effect caused by shield tunnel closely side-passing viaduct foundation is studied based on an actual project. Method Relying on the project of Hefei Metro Line 5 in which the shield tunnel passes the pile foundation of the viaduct on the side, a three-dimensional numerical model is established to analyze the horizontal displacement,the longitudinal displacement and the settlement pattern of the pile foundation caused by shield construction. Result & Conclusion The research results show that the horizontal displacement at the pile bottom presents dynamic changes of leaving, approaching and leaving the tunnel. The horizontal displacement of the pile body is similar to a C shape flexture curve. The displacement increases first and then decreases along with the pile depths, and the extreme value is located at the pile depth of 9~10 m. The longitudinal displacement at the pile bottom (parallel to the tunnel axis) shows a bimodal curve. After the shield passing the pile foundation, the pile body undergoes longitudinal deformation in the opposite direction of the excavation. After the shield passing through the pile foundation for 12m and further, the horizontal displacement of the pile body in longitudinal direction rebounds, indicating that the influence of shield tunneling on the longitudinal deformation of the pile foundation is reversible to a certain extent. The settlement of the pile foundation presents a steep trend. The closer the pile foundation at the same side is to the tunnel, the greater the settlement. Moreover, the excavation of the far side tunnel will cause secondary settlement of the pile top. The maximum settlement occurs at the bottom of the No.4 pile foundation, and the settlement value is 4.94 mm.
Authors and Affiliations
Fenghai MA, Qi WANG, Pan YAN
Experimental Study of Rail Beam Joint Bolt Loosening Impact on Rail Structure Vibration in High-Speed Maglev Maintenance Base
Objective During the train debugging process, significant vibrations may occur in the steel rail beams of high-speed maglev maintenance bases due to their unique structural characteristics, potentially leading to bolt lo...
Analysis of the Digital-Intelligent Development of Medium and Low Capacity Rail Transit System
Objective With the rapid development of rail transit technology and intelligent improvement of urban public transportation, the digital and intelligent concept extends and spreads widely in urban rail transit system, gra...
Air Defense Scheme of Airside MRT Vehicle Base in Shanghai Pudong International Airport
Objective The air defense control mode for airside MRT(mass rapid transit system) vehicle base of the airport directly affects the airport air defense safety and vehicle maintenance efficiency. Incorporating Pudong Int...
Research on Switch Machine Fault Diagnosis Based on Integrated Deep Learning
Objective To make full use of fault log data for diagnosing switch machine faults, a fault diagnosis method based on integrated deep learning is proposed. Method By analyzing the textual data of switch machine faults and...
Simulation Analysis of Jet Noise from High-speed Railway EMU Main Circuit Breaker Switching Valve and Noise Reduction Measures
Objective The jet noise generated by the main circuit breaker switching valve of high-speed railway EMU is excessively high, which seriously affects passenger comfort. Therefore, it is essential to study effective noise...