October 27th, 2022
Singapore: a year on, work is progressing on the CR116 project
In July 2021, an internal consortium, comprising Soletanche Bachy International, Bachy Soletanche Singapore and Bessac, with our partner Gammon, was awarded the CR116 contract to construct the Ang-Mo-Kio metro station and other related structures. What stage are we at a year on? Discover the latest worksite progress, including a number of process optimisations and innovations.…
A little over a year ago, the internal consortium celebrated winning the design-and-build contract to extend the Singapore metro’s Ang Mo Kio station. This project forms part of the extension of the Cross Island Line, the eighth line on the metro network.
The project includes delivery of the station, located in the heart of the very dense Ang Mo Kio district, as well as its six entrances, its two underpasses created using the “pipe jacking” (microtunneling) technique, its cut-and-cover tunnel and its two tunnels created using a 7.2 diameter tunnel boring machine (TBM). The contract also includes upgrade and modification of the existing aboveground station, all by the end of 2029.
The internal consortium is positioned as a general contractor on this large-scale project.
What stage are we now at, 14 months on from signature of the CR116 project?
The project involves several technical challenges. First, creating a 19m-diameter and 40m-deep double shaft for the TBM, through granite. The Soletanche Bachy consortium differentiated itself and offered an innovative variant. The initially planned construction using secant piles presented potential risks and additional costs, so the teams proposed the construction of the shafts using diaphragm walls. This move paid off since, with 50% of the work now complete, production rates are on target and our customer has congratulated us! From January, grouting will begin inside and outside the shafts, before they are then excavated for assembly of the first TBM in 2024.
Detailed studies are still in progress at the station and the current challenge is to obtain approvals from the authorities to begin the temporary retaining walls (before the end of 2022), then the entrances’ diaphragm walls (early 2023), paving the way for the first excavations before summer 2023.
Meanwhile on-site, teams are busy with preparatory work on each of the six entrances, dismantling of the pedestrian bridge, earthworks on the hill and construction of the test piles. Significantly, we are using AVUS software (developed by VINCI) to enable our worksite teams to view all the underground networks in augmented reality. This revolutionary tool fits perfectly into our “excavation permit” process (a checklist signed by all parties to avoid hitting a network) and significantly reduces risk for our worksite teams.
The consortium entities’ employees are gradually learning to work effectively together, with the absolute priority being the safety of all employees and the public.
