September update for the Forrestfield Airport Link

Welcome to September’s Forrestfield-Airport Link project update.

With TBM Grace now tunnelling and Sandy soon to launch, production of tunnel segments has ramped up over the past month. The facility, located two kilometres from the Forrestfield dive structure, is capable of producing 132 segments per day. These segments are then stored at the Forrestfield site and transported, as required, by multi-service vehicles down into the TBMs. Approximately 54,000 segments will be produced over the life of the project to support tunnelling operations.

Meanwhile construction of the underground station boxes at Airport Central and Belmont is progressing well, with both sites on schedule to receive the TBMs early and mid-2018 respectively.

Segment production in full swing
On Wednesday 16 August, Premier Mark McGowan and Transport Minister Rita Saffioti toured the project’s segment facility in Forrestfield. The facility, opened in June, produces six unique segments which fit together to form a single ring. There are 9000 rings required to build the two eight-kilometre long tunnels. While onsite the Premier tried his hand at pouring the concrete for one of the segments but from here on it will be over to our 60 plant workers.

To find out more about segment production visit the project website.

Sandy’s time to shine
Our TBM competition winners joined us onsite at Forrestfield last week for the official naming ceremony for our second TBM, Sandy.  All sections of Sandy, named after the sandgroper, have now been lowered into the dive structure and assembly and testing of the machine is progressing well. It is expected that Sandy will be ready to begin tunnelling by the end of the month.

A special information session was held at the project’s briefing centre in late August for students who entered the competition to name and decorate the TBMs. More than 40 people attended the session to learn more about the TBMs and how they work. Thank you to all the students who participated and congratulations again to our competition winners.

Changes at Forrestfield site
The Forrestfield construction site is now operating 24/7 to support the tunnel boring machines. The site houses facilities needed to operate the TBMs, including infrastructure for slurry separation, grout production and water treatment.

With these facilities operational, focus will shift to the realignment of Dundas Road, between Berkshire Road and a point between Maida Vale Road and Poison Gully Creek. Dundas Road will remain open until the realignment is completed and the majority of the one-kilometre realignment works will be conducted without impacting traffic.

 

Backfilling at Bayswater continues 
The 500m long retaining wall, constructed adjacent to Railway Parade in Bayswater, is now complete and backfilling is well underway. The backfilling requires 12,000m3 of spoil to be used to create an even gradient for the temporary Midland line.

Once gradient is achieved track works will commence. A series of out of hours’ activities are required over the coming months for the installation of screw piles and the construction of track and overhead line equipment for the temporary rail alignment.

Early works for the southern construction site in Bayswater are also now underway. The shared pedestrian and cycle path along Whatley Crescent (between Slade and Newton streets) has recently been closed to enable the construction of the Bayswater Junction at this site. This section of PSP is scheduled to remain closed for the next two years.

To find out more about the PSP changes visit the project website.

Building emergency egress shafts 
Emergency egress shafts provide emergency exit points for passengers along the tunnel alignment. In the event of an incident, commuters will access the emergency egress shafts using the cross passages and walkways within the tunnel. They will then be able to use either the stairs or the lift contained within the emergency egress shaft to reach ground level emergency muster point.

There are three locations where shafts are being built along the tunnel alignment:

• Abernethy Road, Forrestfield – diaphragm walls have been completed. Excavation of soil within the structure will begin in October.
• Airport West – construction of the diaphragm walls commenced in late August and will be ongoing until early October.
• Wright Crescent, Bayswater – clearing and topsoil removal commenced this week to establish the construction site. Diaphragm wall construction will begin in mid-October.

source: Government of Western Australia.