On last June, we provided an update on the progress of the City Rail Link project. Since then, the teams have been facing another lockdown (mid-August to mid-September), but stepped up their work when they returned in order to stay on target.
For the C5 part, foundation work is almost complete:
- The diaphragm wall for the eastern crossover structure was completed in early July, leaving only the tunnel connection part remaining.
- Deep Soil Mixing was completed in mid-July
- The piles for the first phase were recently completed and the opening of the new track is now expected for the launch of phase 2 of the project, apart from a small number of structures due in the coming weeks.
The worksite’s activity profile has therefore changed considerably since last June with:
- Excavation works inside the retaining structures, made up of piles and diaphragm-wall panels. These earthworks are undertaken together with shotcrete activities.
- Construction of our main civil engineering structure: the eastern flyover. A 207m-long structure comprising two to three rows of diaphragm wall, with two to three levels of slab to be created using a “top-down” process, allowing the NAL North line (MC10) to pass over a future track linking to the future tunnel (MC50) and also housing a second connection track (MC60).
- delivery of the platform for the new MC10 track to our track/system colleagues (C7) on mid-November for installation of all the rail infrastructure (ballast, rails, overhead power lines and signalling) as well as the operating systems, with the track set to come into service in January 2022 during the Christmas break (Christmas Block of Line).
- once rail traffic has switched to the new track, we will work on the other side of the existing tracks, with a new retaining wall phase (piles, sheet piles, ground improvement and L-shaped walls).
Find out more about the project’s progress in pictures, from before the start of lockdown, of the southern zone of C3/C5/C7, i.e. Mount Eden station (which is also the starting point and rear base for the tunnel boring machine), and connection to the existing line.
Our “Dame Whina Cooper” tunnel boring machine has passed the 800m mark and has just reached K Road station. At that point, she has covered a quarter of the total length.
- The tunnel being dug at KRD (intermediate station) is more than 85% complete and the first cavern (platform) is ready for the newly arrived tunnel boring machine, while the second will have been completely excavated by the end of November. The formwork for the final lining of the caverns has recently been completed in Turkey (with the help of our local colleagues to supervise manufacturing). The earthworks for the two access shafts (created using a “top-down” methodology) have reached the platform roof. The slabs for the first two underground levels are finished.
- At Aotea station (northern end of the project), the roof slab (ground level) is 30% complete, the intermediate level 15%, and the earthworks will soon be completed for the arrival of the tunnel boring machine. After a switch of traffic, foundation work has resumed in the northern area (piles and diaphragm walls) and should be finished by the end of the year. The main entrance superstructure is now out of the ground.
- The underground structures are progressing at Mount Eden station (the junction with the C5 works), with the future semi-underground platform 50% complete and delivery of the western flyover to the rail teams due at the end of November. An important stage was the diversion of a potable water pipe supplying Auckland which passes through the future station at track level and has just been successfully completed!
Congratulations to all the teams in the Link Alliance consortium, including and March Construction.