TBM Grace

Tunnel boring machine (TBM) Grace arrived at Redcliffe Station last month, breaking through the one-metre-thick eastern station box wall to a cheering crowd of excited team members.

The TBM’s 15-strong crew guided her through the dry box, a structure located adjacent to the station box and designed to correctly pressurise the machine’s breakthrough. She made her final entry into the 12m-deep underground station around 2pm on May 9. This is the second time that TBM Grace has surfaced since beginning tunnelling at Forrestfield mid-2017 – a major milestone for the project. Click here to watch her big moment.

Since leaving Airport Central Station last year, TBM Grace has tunnelled 2.6km and built more than 1600 concrete rings. She has now been moved through the station box and will soon be ready to begin the final leg of her underground journey.

Main escalators installed at Airport Central

Another major milestone has been achieved at Airport Central Station with the installation of the main passenger escalators now complete.

The triple escalator system, which is 35m long and 15m high, will connect the Skybridge to the concourse level. Once operational, it will take 55 seconds to travel from top to bottom and a total of 8200 passengers can be transported per hour. It is the longest single-span uninterrupted escalator in the Southern Hemisphere.

View footage of the escalator installation here.

At platform level, concrete has been cast to form the walls on both sides of the platform, with sections of the wall left open to allow for the movement of multi-service vehicles (MSVs) while these continue to deliver segments through the tunnel to TBM Sandy.

Redcliffe Station has welcomed TBM Grace

Recent works at Redcliffe Station were centred around the scheduled maintenance of TBM Grace, including testing of mechanical and electrical equipment, replacement of worn cutterhead tools and the installation of a brand new screw conveyor. The 16m-long screw is used to transport excavated material away from the front of the machine.

TBM Grace has also received a number of visitors since resurfacing, including her namesake six-year-old Grace McPhee, as well as Premier Mark McGowan and Transport Minister Rita Saffioti, who were on site to announce this major milestone for the project.

Preparation works are now underway for the TBM to leave the station box in the coming week. She is already lined up at the western station box wall and installation of the thrust fame, used by the machine to push forward, has commenced.

At the site of the station’s future 500-bay car park asphalt works are ongoing and the first prime coat has been sprayed for both the parking area and the entry.

Structural works underway at Forrestfield

At the northern end of the Forrestfield site, just above the tunnel entries, bricklaying has been completed for the first level of the tunnel portal building, allowing for the concrete slab of the next level to be poured.

Also above ground, and clearly visible from Dundas Road, is a large scaffolding structure in the centre of the station platform. The structure was erected to support formwork for the suspended concourse slab. With the concrete slab now poured, focus has shifted to preparation works for the installation of the 11m-long escalator connecting the concourse and platform levels.

Construction of the steel structure for the station's lower roof has also commenced, with the main roof expected to be installed in the second half of this year.

Earlier this week Transport Minister Rita Saffioti announced the Metropolitan Redevelopment Authority’s (MRA) Midland Redevelopment Area will extend to include areas around Bayswater and Forrestfield stations and become METRONET East. More information on this development is available here.

Bayswater Junction pours near completion

With winter rains finally here, concrete pours for the dive structure at Bayswater have been moved under cover. One of the remaining sections of the base slab, located underneath the Midland Line overpass, was finalised this week and is now curing. The final three pours are scheduled to be completed by the end of the month.

Meanwhile work has commenced to construct the noise wall located adjacent to Whatley Crescent. A mechanical rig is currently onsite drilling the 3m-deep holes required to secure the post and panel structure to the ground. The project team recently consulted with the local community regarding the colour of the noise wall. A choice of three individual colours or a pattern using all three colours intermittently was presented and, after all votes were tallied, the community decided in favour of the alternating pattern. The wall panels will be painted once installed, with works due to be completed around the end of June.

Second cross passage fully excavated

The project's second tunnel-to-tunnel cross passage, located east of Perth Airport's terminals 1 and 2, has now been fully excavated. After spraying the cross passage's walls with concrete and installing steel fixings, waterproofing works were completed. Construction of the concrete base slab for the 10m-long link between the two tunnels will now occur, before the final concrete lining can be installed.

While these works are ongoing until mid-July, a second cross passage crew has cut through the diaphragm wall at Airport West Emergency Egress Shaft and commenced excavation to TBM Sandy's tunnel.

Click here, here and au/34 for the tunnelbuilder archive. Also visit https://www.forrestfieldairportlink.wa.gov.au/. 23/19.