N109A - Completion of Exit 2 subway

 

June 2025 - Completed Rectangular Tunnel Boring Machine drive for Exit 2 subway.
Image from LinkedIn

This month, a milestone has been achieved at contract N109A for the construction of Teck Ghee station - the second exit subway undercrossing Ang Mo Kio Avenue 1 has been completed! As part of the station's construction, contractor Shanghai Tunnel Engineering Co (STEC) had utilised a rectangular tunnel boring machine (RTBM) to construct 2 subways linking Exits 2 and 3 within Bishan-Ang Mo Kio Park to the station box.

With the latest breakthrough at the Exit 2 subway, both drives have since been completed. The final segments are likely to be loaded in and the entire consist shoved till the front of the RTBM emerges fully into the reception shaft. Following this, the RTBM will be dismantled and decommissioned, potentially being used for other projects.

June 2025
Image from LinkedIn

June 2025
Image from LinkedIn

June 2025
Image from LinkedIn

If you're curious how an RTBM works, here are some videos on the process which is slightly different than that of a standard TBM. Instead of the machine propelling itself forward by thrusting against completed tunnel rings, a piston shoves the entire completed tunnel segments forward. This technique is known as pipe jacking, which is why the banner in the first image states "RPJM completion" - RPJM standing for Rectangular Pipe Jacking Machine.

Introduction of Rectangular Tunnel Boring Machine

at Cross Island Line (CRL) Teck Ghee station

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