Bouygues Group: Tung Chung Line – Structural monitoring
the project
The project involves a westward extension of the Tung Chung Line (TCL). It mainly includes there main construction points:
- 1.3km westward rail extension from the existing railway tunnel of Tung Chung Station,
- new Tung Chung West Station near Yat Tung Estate
- Building an emergency egress point (EEP) at Shun Tung Road.
A Tunnel Boring Machine (TBM) would be used to construct the tunnel betwwen the exisitng station and the new one.
Challenges
The challenge of this project for UBY is to supply, install, and maintain the instruments needed for effective geotechnical Instrumentation and Monitoring (I&M) systems. These systems ensure the safety and stability of the project using advanced monitoring solutions to protect surrounding infrastructure, track ground conditions, and support the successful completion of the extension.
With tunneling and excavation taking place in complex ground conditions, the focus is on monitoring the ground movement, the structural stability, and the vibrations. Advanced sensors and real-time monitoring platform are used to protect nearby infrastructure, maintain safety, and ensure the project progresses smoothly with minimal disruption.
Duration of project: May 2023 - 2029 (est.)
uby solution
Machines will operate under existing buildings and structures and the MTR Corporation needs to ensure these projects do not impact any neighbouring facilities and buildings.
Measurements of surrounding structures
We use topographic prisms to measure deformations (in 3D), and façade inclinometers to measure tilts on buildings within the site’s Zone of Geotechnical Influence.
We installed automatic total stations, vibration sensors and tiltmeters to obtain continuous measurements of all the prisms on the surface (buildings, MTR tracks) and in the station box, and TBM launching and retrieval shafts.
All measurements collected are available on our uMonitor platform. Our data visualization tool enables us to monitor the site environment in real time, and to keep a constant eye on any impacts. It also enables frequent, up-to-date reporting. An alert system is also available.
Benefits for the worksite
Data collected and real-time alerts are sent to the engineering team automatically in case of any abnormal movement to any surveilled structures. This helps the geotechnical engineering team ensure the actual impact of the operation complies with calculations made beforehand and thus better steer the progress of the Tunnel Boring Machine.