The same set of work has commenced in Tunnel One, where more than 15 per cent of skeleton track has been assembled.
After consultation with international experts, the most suitable method to repair a 26m-long section of Tunnel One was decided earlier this year. The tunnel was damaged when a leak developed at the first tunnel-to-tunnel cross passage approximately 200m north of the High Wycombe Station site in September 2018. The pressure of the groundwater, and the associated loading, caused localised distortion to the tunnel shape and movement of the segments which make up the tunnel lining.
The method chosen to rectify the distorted section of tunnel has been tried and tested across the world, including in the London Underground. A spheroid graphite iron lining is being installed to correct the tunnel alignment and ensure the required strength, durability and water tightness is achieved.
The construction of the cross passage structure is complete and more than 50 per cent of the new lining has been installed. Rectification works are expected to be completed by the end of the year. This will free up the last section of tunnel for track laying.
Bayswater tunnel portal taking shape
At the tunnel entry, about 11m below surface level, works are ongoing on waterproofing the tunnel sealing rings.
Just a few metres above, the sheeting of the portal building's lower roof has recently been completed and installation of the upper roof structure is ongoing. The building is now clearly visible from surrounding areas.
At the western end of site activity is focussed on the permanent tie-in of the Midland and Airport lines. The majority of works will be conducted during the day, however, given the proximity to live rail, this is not always possible. Therefore a second set of night works is scheduled for October 18 to 23.
Raising the roof in Redcliffe
Roof works are progressing well at Redcliffe Station, with more than half of the steel frame standing and the first glazing for skylights scheduled to be installed later this month. The sheeting on top of the steel frame is expected to be in place by the end of November.
The second of two passenger staircases is currently being assembled at ground level, with installation imminent. All station escalator frames have also been assembled, however still require fit-out.
Further to the south, light poles are popping up in the station's 500-bay car park, and works on the roundabout at Second Street and Boulder Avenue are expected to be finished in early November.
Airport Central Station receiving 'face lift'
The installation of building finishes at Airport Central Station is ongoing in the form of ceiling panels, aluminium cladding to atrium walls, cladding of escalators and lift shafts, and external glazing along the structure's outer walls. The latter is nearing completion, however three glass panels will remain open so equipment can be lowered to the concourse level.
All the way on top of the building, crews have recommenced the installation of roof sheeting, which is being moulded into shape on site.
Other activities include cable pulling, installation of permanent and emergency lights, painting of walls and epoxy painting of floors.
High Wycombe Station's eyes on the track
A new set of work is underway at the portal and stowage buildings, where CCTV cameras have be affixed to external walls. Not much longer and big brother (aka the surveillance team) will be watching!
With the completion of the electrical substation along Maida Vale Road the time has come to call local budding artists aged 12 to 25 to participate in a Youth Art Project. Facilitated by the Public Transport Authority's Right Track program and the City of Kalamunda, a 40m-long section of wall around the substation will provide a blank canvas for a piece of art, providing a unique entry to the station precinct. More information is available on the Right Track website.
Cross passages nearing completion
For the very last time the cross passage team has turned on the chiller plant to freeze the ground for the final cross passage excavation. Once complete early next year, the alignment will comprise 12 tunnel-to-tunnel connections and three tunnel-to-egress shaft links for emergency and maintenance access.
Main works in the emergency egress shaft (EES) space include installation of the lift at Abernethy Road EES, cable pulling at Airport West EES and final touches to the stairs and lift frame structure at Wright Crescent EES.