CR105 - An update from Q1 2024

 

13 March 2024 - A photo of the Minister of Transport, Mr. Chee Hong Tat, with LTA's senior
management as the ceremony for the launch of TBM Izanami.
Source: CREG

Thus far, the Cross Island Line (CRL)'s worksite have all been about creating big holes in the ground. It's been rather similar across the different sites - hardly the interesting stuff of the Jurong Region Line (JRL) where you can see the viaducts coming nearer and nearer to you with each visit. This time, though, we're in for a different kind of update on the CRL. Hopefully one that would be of more interest. Word has been rather mum when it comes to tunneling work along the line. Has it begun yet? Has it not? Not a peep from client Land Transport Authority (LTA). But we've come across some photos of late that suggest, perhaps, maybe, tunneling works might have begun quietly over at Changi.

Contract CR105 was awarded to a joint venture between construction veteran Taisei Corporation (Circle Line's Farrer Road, Botanic Gardens & Caldecott stations, Downtown Line's Downtown station & Thomson-East Coast Line's Marina Bay station) and relative new-comer China State Construction Engineering Co (Downtown Line's Geylang Bahru & Kaki Bukit stations). The tunnel boring machine (TBM), Izanami, first came into view during the factory acceptance tests which were conducted some time in February 2023. Izanami is one of the largest TBMs to be used locally, measuring at 12.66m in diameter. The large, single bore tunnel will eventually measure approximately 12.22m when completed.

February 2023 - The 12.66m TBM at the factory acceptance test ceremony.
Source: CREG

February 2023 - TBM Izanami in the factory at the end of the acceptance tests.
Source: CREG

Subsequently, in October 2023, Izanami was lowered into the contract CR105 launch shaft which is located to the west of the Aviation Park station. Izanami will bore a tunnel of 3.2 km from her launch shaft to Loyang station underneath Loyang Avenue. This journey will see the TBM crossing underneath some key infrastructure in the vicinity of Changi Airport, a challenge for the contractor. Working near the airport also comes with additional challenges of height restrictions as airplanes landing and taking off would need sufficient clearance over vertical equipment to prevent collisions or navigational issues.

October 2023 - The TBM's cutterhead being hoisted into position.
Source: CREG

October 2023 - Enormous cranes were required for the lifting effort.
Source: XCMG

With the components of the TBM lowered into the launch shaft, it appears that a launch ceremony was held in March 2024 to commemorate the start of tunneling works under contract CR105. Tunneling works here also represent the beginning of such works anywhere across the 29km length of the first phase of the CRL.

October 2023 - The TBM cutterhead lowered for assembly with the rest of
the TBM within the shaft.
Source: XCMG

13 March 2024 - A view of the rear of the TBM within the launch shaft.
Source: CREG

With the launch of the TBM at CR105's launch shaft, tunneling works for the CRL have begun without much fanfare. The single bore tunnel will use some innovative methods of construction locally. These include the use of precast walls to be installed within completed sections of the tunnel to separate the two trackways that will carry trains in opposite directions. This separation allows each trackway to be isolated from the other, improving fire protection for passengers among other benefits.

This post will also be available on Instagram & Facebook on 24 May 2024.