Analysis of Bearing-settlement Characteristics of Extra-long Bored Piles in URT Deep Soft Stratum Underground Station
Journal Title: Urban Mass Transit - Year 2024, Vol 27, Issue 8
Abstract
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 necessary to conduct an in-depth study of the bearing-settlement characteristics of extra-long bored piles (hereinafter as EBP) with void in the upper part. Method Using an urban rail transit double-line L-shaped cross transfer station as example, the influencing factors of the bearing-settlement characteristics of EBP are analyzed through static load tests by self-balanced method and numerical modeling. The relationship between the bearing characteristics of EBP and the pile length, pile stiffness, and pile diameter is explored. Result & Conclusion The static load test results indicate that, during the incremental loading in load box of EBP with void in upper part, both the pile top displacement and the displacement growth rate gradually increase, with pile top exhibiting displacement rebound phenomenon during unloading. Numerical simulation analysis shows that the axial force of EBP shaft decreases gradually from pile top to pile end. When the pile top is under ultimate load, the axial force at pile shaft upper part is significantly greater than at pile end. Changes in pile shaft length and stiffness affect the bearing-settlement characteristics of extra-long piles with void in upper part, while changes in pile shaft stiffness have little impact.
Authors and Affiliations
Haixing ZHU, Chunlin DING, Yuhe LU, Guiying LI
Keywords
Related Articles
- EP ID EP742696
- DOI 10.16037/j.1007-869x.2024.08.025
- Views 42
- Downloads 0
Research on Failure Processing of Axle Counter in CBTC System
Objective The communication-based train control (CBTC) system usually uses the axle counter to provide train auxiliary positioning functions. However, in the case of axle counter failure, if it is always processed as "oc...
Fracture Cause Analysis and Treatment Effect for Urban Rail Transit Vibration Damping Track DI-type Elastic Strip
Objective Elastic strip is a critical component of rail vibration reduction fasteners, its mechanical performance and fatigue-load bearing capacity are crucial for urban rail transit train operational safety and track se...
Influence of Metro Shield Left/Right Line Tunnel Parallel Under-passing on the Defor-mation and Stress of Existing Open-cut Highway Tunnel under Deformation Joint Working Condition
Objective To ensure the successful implementation of metro shield tunnel parallel under-passing through the existing open-cut highway tunnel project under deformation joint condition, it is necessary to analyze the defor...
Optimization Scheme of Internal Circulating Heat Dissipation System for Tram Ground Charging Device
[Objective] To solve the problems of unstable shell protection performance, complex HD (heat dissipation) system configuration, and low HD efficiency existing in current tram ground charging devices, a scheme of ICHD (in...
Influence Law of Vertical Layer-incremental Foundation Pit Excavation on Existing Station Structural Deformation
Objective Construction disturbances from nearby excavation of foundation pit can cause significant deformation of existing stations in operation, thereby affecting the normal operation of trains. Therefore, it is necessa...