scholarly journals Numerical analysis on surface settlement in parallel rectangular pipe jacking construction

2021 ◽  
Vol 2044 (1) ◽  
pp. 012174
Author(s):  
Jianwu Gong ◽  
Kang Zhang ◽  
Peilin Qi
Keyword(s):  
Numerical Analysis ◽  
Surface Settlement ◽  
Pipe Jacking

3D Numerical Analysis of Soil Structure Interaction Behaviors of Pipe Jacking Construction

2012 ◽  
Vol 204-208 ◽  
pp. 534-538 ◽  
Author(s):  
Wen Tsung Liu ◽  
Xu Yan Lu
Keyword(s):  
Numerical Analysis ◽  
Soil Structure ◽  
Soil Improvement ◽  
Ground Movement ◽  
Science Park ◽  
Tunnel Excavation ◽  
Contraction Ratio ◽  
Pipe Jacking ◽  
Interaction Behaviors ◽  
Plaxis 3D

This study is analyzed by numerical analysis using finite element method program of Plaxis-3D Tunnel at Kaohsiung Science Park in Taiwan. It probes the risk of tunneling procedure adopting pipe jacking construction (PJC) with man–made excavation. The main parameters of numerical calculation in this research include advancement size, soil improvement ratio and void contraction ratio, etc. Those parameters are calculated to displacement and stress distribution and we get ground movement, settlement at crown and heave at invert of tunnel excavation to assess the security. This study finds that it is safe by excavation using PJC with man-made while the gap has to be less than 38mm. Actually, the gap is 100 ~ 150mm under PJC with man-made, and it will result in high risk. Therefore, the PJC with shield has more security than other methods through monitoring ground settlement.

scholarly journals Numerical Analysis on the Performance of the Underwater Excavation

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Bo Li ◽  
Cangqin Jia ◽  
Guihe Wang ◽  
Jun Ren ◽  
Gaofeng Lu ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Retaining Wall ◽  
Lateral Wall ◽  
Surface Settlement ◽  
Design Parameters ◽  
Analysis Model ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Wall Deflection ◽  
Total Settlement

Based on the Yongdingmen Station of Beijing Metro, the underwater excavation method for deep foundation pit was introduced. This study constructed a numerical analysis model to analyze the performance of surface settlement and lateral wall deflection in the process of underwater excavation. Results showed that this method was better to control the surface settlement and lateral wall deflection compared with other dewatering excavations. In detail, most of the surface settlement was caused during the dry excavation stage and dewatering excavation stage while the deflection caused by underwater excavation only accounted for about 10% of the total settlement. Besides, the maximum settlement occurred 0.25∼0.5 H e behind the retaining wall and the value was 0.04% H e . Similar to the result of the surface settlement, most of the lateral wall deflection had been completed before the underwater excavation, which only caused about 7% of the total deflection. The maximum wall deflection and its location were approximately 0.06% H e and 0.5 H e , respectively. Moreover, a series of 3D numerical analyses were studied on the design parameters of the underwater excavation method. This study can be used as a reference for general performance and structural design of foundation pits with underwater excavation.

scholarly journals Numerical analysis and application of the construction method for the small interval tunnel in the turn line of metro

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042093206 ◽  
Author(s):  
Zhanping Song ◽  
Xiaoxu Tian ◽  
Qi Liu ◽  
Yuwei Zhang ◽  
Heng Li ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Construction Method ◽  
Surface Settlement ◽  
Underground Excavation ◽  
Small Interval ◽  
Resource Configuration ◽  
Construction Methods ◽  
Initial Support ◽  
Left And Right

The surrounding rock may become unstable or even fall down and the initial support may crack and be destroyed when the construction method of the underground excavation tunnel is not properly selected in the turn line of metro. . A section of the Santunbei turn line of Urumqi Metro Line 1# was taken as the engineering background. The proposed construction method was analyzed by numerical simulation. Numerical analysis shows that the final surface settlement caused by the proposed construction method is 3.0 mm and the horizontal convergence is 3.2 mm. It also turns out that the proposed construction method causes less deformation, and the method can be applied to the construction of the small interval tunnel in the Santunbei turn line of metro. The rationality of the method and numerical model was further verified by comparison between the monitored data of surface settlement, horizontal convergence and vault sinking, and numerical simulation results. Finally, the deformation and stress of the six construction methods were compared. The deformation and stress caused by the six construction methods are almost the same. It indicates that the construction spacing between the left and right tunnels does not affect the safety of tunnel construction. Therefore, the appropriate construction spacing could be selected according to the resource configuration, instead of deformation and stress.

Numerical Analysis on Interaction Induced by Crosswise Tunneling

2014 ◽  
Vol 580-583 ◽  
pp. 1076-1080
Author(s):  
Peng Lu Gan ◽  
Xiao Wu Tang ◽  
Wen Ming Shen ◽  
Heng Yu Wang
Keyword(s):  
Numerical Simulation ◽  
Numerical Analysis ◽  
Surface Settlement ◽  
Urban Rail Transit ◽  
Monitoring Data ◽  
Rail Transit ◽  
Reinforcement Effect ◽  
3D Numerical Simulation ◽  
Air Defense ◽  
Urban Rail

A position conflict exists between Harbin Urban Rail Transit Line No.1 and the branch tunnel of "7381" civil air defense tunnel. Intense tunnel interaction occurs when Line No.1 is perpendicularly tunneled across the branch tunnel. The investigation of the interaction is necessary. A 3D numerical simulation is established using FLAC3D and the vault deformation around the tunnel intersection is analyzed. The vault settlement of Line No.1 increases by 1.4 times during crosswise tunneling, while the vault settlement of branch tunnel increases 21.0mm in addition. The affected region of the tunnel intersection is further revealed. The affected length of the vault of Line No.1 and branch tunnel is 7.5 times the diameter and 6 times the width respectively. In combination with monitoring data, the reinforcement effect is studied at last. Both the vault settlement and surface settlement are well controlled in the tunnel intersection.

Sign in / Sign up

Export Citation Format

Share Document