Expected to arrive at Bayswater Junction within the next month, tunnel boring machine (TBM) Grace is leading the race and is bound for her third and final breakthrough.
TBM Sandy is tunnelling less than a kilometre behind her sister, and together they have installed more than 49,500 tunnel segments to date!
The end of tunnelling will bring a number of changes for the project, such as the demobilisation of the slurry treatment plant in Forrestfield, as well as major progress in fit-out works within the tunnels.
A number of lengths of rail have already been delivered to Forrestfield, and construction of the first stage of the track slab within the tunnels is more than 40 per cent complete. The second stage of the track slab, including installation of the rail, will commence mid-year.
Bayswater preparing for momentous occasion
Preparation works for the arrival of the TBMs are taking centre stage at Bayswater Junction, with the last component – jet grouting adjacent to the dry box – underway.
The dry box adjoins the Bayswater tunnel portal and is designed to correctly pressurise the TBMs' final breakthroughs.
Following their breakthroughs, the machines will be dismantled and craned out of the dive structure in sections. Some parts will be returned to the manufacturer in Germany for reuse, others will become scrap metal.
As part of these works, a section of the principal shared path (PSP) along Guildford Road had to be shifted, to allow for protection of services located underneath the PSP. The temporary alignment will stay in place until the last part of TBM Sandy has been removed from site.
At the western end of site, delivery of rail segments is scheduled for this month. A total of 38km of rail is required for the full alignment.
Redcliffe Station car park complete
The construction of the 500-bay car park at Redcliffe Station has been completed for now, with final touches such as line markings and landscaping to be done closer to the station’s opening. Work to date has included fence installation, building a new access point, preparing the foundation and installing a motorcycle shelter.
Commencing within the next few weeks will be the construction of a roundabout at the intersection of Second Street and Boulder Avenue. Works will take up to four months and are necessary to provide additional access to the car park.
Considerable progress has been made within the station box, where the western mezzanine level is nearing completion. Works on closing the gap within the eastern end of the ground slab are underway, with installation of precast planks almost complete.
While tunnelling is ongoing, 24-hour operations will continue at the Redcliffe site.
You can view an animation of the future Redcliffe Station here.
Airport Central Station a hive of activity
Construction is ongoing at all levels of Airport Central Station. At concourse level, temporary struts are being removed and metal decks that will hold the tunnel ventilation system are being installed.
The emergency staircase at ground level has recently been completed, and dry walls for a number of utility rooms located underneath the Skybridge entrance are being erected.
Also at ground level, following delivery of the first steel components, trusses for the 51m-wide station roof are being assembled and are scheduled to be craned into place in the first quarter of 2020.
Forrestfield Station raising the roof
Following the completion of the station’s roof steel structure, installation of red roof sheeting is now underway. Adding a bit of color to the scene and blending in with the earthy tones of the nearby Darling Ranges, the distinctive station roof will be visible from surrounding areas and clearly identify the entry point to Forrestfield Station.
Works to close the final section of the station’s main retaining wall are ongoing. Formwork is being installed to counterforts, to be followed by a number of concrete pours. Once complete, backfilling of the area can commence.
New in 2020 is the construction of the traction power substation, located along Maida Vale Road. The traction power system supplies electric power to the suburban railway network, and the Forrestfield substation will house a single traction transformer. From here, electricity will be fed to the overhead wiring system.
First emergency egress shaft closed up
Works are most advanced at Abernethy Road Emergency Egress Shaft (EES), where the roof of the upper ancillary building – the building erected on top of the shaft – has recently been installed.
Wright Crescent EES holds second place with the building structure adjacent to the shaft in place. The upper building will be erected following construction of the cross passages between shaft and tunnels.
With Airport West EES still hosting the cooling towers for cross passage ground freezing works, building works will not commence in earnest until the second quarter of 2020.
The cross passage count still totals five, with cross passages Juliet and Papa nearing completion.