Cause Analysis and Countermeasure Study on Significant Deformation of Chengdu Metro Foundation pit Retaining Piles
Journal Title: Urban Mass Transit - Year 2024, Vol 27, Issue 1
Abstract
[Objective] The complex environmental and geological conditions surrounding metro foundation pit construction can easily lead to accidents. It is necessary to analyze the reasons for significant deformation of foundation pit retaining piles and propose targeted reinforcement measures. [Method] Taking a metro station foundation pit of pile-anchor supporting structure adjacent to old buildings in Chengdu as engineering background, the causes of significant deformation of the retaining piles during foundation pit construction are analyzed and reinforcement measures to control pile deformation are proposed. Using the Harding-soil second-order advanced constitutive model, the feasibility of following measures after retaining pile deformation such as counter-pressure surcharge within the pit, steel pipe piles for the outer slope of the pit, and reinforcement with two additional anchor cables before re-excavation are studied. [Result & Conclusion] Simulation results and field measurements indicate that the accumulated displacement of the retaining piles is 77.77 mm. After implementing reinforcement measures following significant deformation, the horizontal displacement of the retaining piles can be controlled within 53 mm. The consistency between the simulated and field-measured results of the pile horizontal displacement curve change law is evident. Actual construction results demonstrate that the deformation control effect of the foundation pit is significant after adopting reinforcement measures, with no widespread deformation occurring in subsequent construction processes.
Authors and Affiliations
Xue LI, Fengjuan GENG, Weixing ZHAO, Fangli LI, Yuan JIANG
Development and Application of Automated Assembly Testing Production Line for EMU Air Springs
[Objective] As the core component of EMU (electric multiple units) bogie system, the performance condition of air springs is directly linked to the operational efficiency and safety level of EMU. Therefore, it is essen...
Simulation Analysis of A Metro Station Construction in Shenzhen with Small TBM Advancing Excavation Followed by Large TBM Enlargement
[Objective] The new technique of small-diameter TBM (tunnel boring machine) advancing excavations followed by large-diameter TBM enlargement is used for the first time in the construction of Tumor Hospital Station on She...
Personnel Intrusion into Construction Area Warning System Based on RFID and Binocular Vision in Vehicle Base
Objective Construction management at urban rail transit vehicle bases typically relies on work permission and work closure method to control construction safety. However, there is a lack of real-time protective technolog...
Turn-back Interval Time of Normal Conducting High-speed Maglev Trains
Objective Train turn-back interval time is a critical factor influencing the throughput capacity of normal conducting high-speed maglev lines. Due to the significant differences in train operation control principles betw...
Analysis of Influencing Factors and Noise Reduction Effects of Viaduct Noise in City Rail Transit
[Objective] It is aimed to provide advice for viaduct noise control in city rail transit and application of noise reduction measures. [Method] Based on theories of vehicle-track dynamics, wheel-rail vibration radiati...