Subway tunnels displacement analysis due to two different communication channels construction procedures

Area of Science:

• Geotechnical Engineering
• Tunneling and Underground Construction

Background:

• Increasing urban density necessitates extensive underground infrastructure, including communication channels and subway lines.
• Construction of underground structures can lead to significant soil displacement, impacting existing infrastructure and future developments.
• The integration of buildings with subway stations often requires specialized underground communication channels.

Purpose of the Study:

• To numerically simulate tunnel displacement during underground construction stages.
• To investigate the impact of two different communication channel construction procedures.
• To validate simulation results against real-world monitoring data.

Main Methods:

• Numerical simulation was employed to model tunnel displacement behavior.
• Two distinct communication channel construction methods were analyzed.
• Field monitoring of six displacement points on sheet pile walls validated the simulation accuracy.

Main Results:

• Implementing sheet pile walls and struts prior to excavation substantially reduced lateral displacement of the subway line.
• Pre-excavation support measures led to an increase in the vertical displacement of the subway line.
• Wall thickness variations had a more significant impact on lateral displacement than changes in strut cross-section or pile diameter.

Conclusions:

• Pre-installation of sheet pile walls and struts is an effective strategy for mitigating lateral soil displacement during underground construction.
• Numerical simulation provides a reliable method for predicting and analyzing tunnel displacement behavior.
• Optimizing wall thickness is crucial for controlling lateral displacement in underground construction projects near sensitive structures like subway lines.