Photos of the SkyTrain Evergreen Line's massive tunnel boring machine

Dec 19 2017, 10:05 am

Earlier this month, tunnel construction for the SkyTrain Evergreen Line began and was marked by naming the massive tunnel boring machine.

‘Alice’ is responsible for the 2-km tunnel segment that will travel southwest under Clarke Road, as deep as 60-metres from the surface, from Barnett Highway and View Street to just before Como Lake. From Lougheed to Coquitlam Centre, the new line has a total length of 11-kms and will allow passengers to get from end to end in just 15-minutes – on trains that depart every 3-minutes.

The 9.84-metre diameter, 90-metre long machine has a weight of 1,100 tonnes and will only make one pass to build the one tunnel needed to accommodate both the northbound and southbound tracks. The machine will be operational 24-hours a day, seven days a week by S.E.L.I. Canada, which also undertook the tunnel boring contract for the Canada Line.

The tunnel will be bored at rate of approximately 10-metres a day and is expected to reach daylight in approximately a year.

For more information on the Evergreen Line tunnel boring machine and how it works, click here.

The machines’s drilling head has a diameter of 9.84-metres.

Evergreen Line tunnel boring machine
Image: Evergreen Line

The tunnel construction process begins.
Image: Evergreen Line

Material dislodged by cutter teeth flows through gaps in the cutter head into a chamber behind the cutter head inside the tunnel boring machine.
Image: Evergreen Line

Tunnel boring machine’s cutter head weighs 130 tonnes and had replaceable cutting teeth. The red piqued section in the picture is the centre of the cutter head.
Image: Evergreen Line

Inside the tunnel boring machine a ring of hydraulic jacks are used to hold pre-cast tunnel liner rings in place. The jacks are contracted to allow for a new ring segment to be installed and then extended to hold them in place. It also helps push the machine forward.
Image: Evergreen Line

A screw conveyor moves the material removed by the cutter head back to the tunnel boring machine’s trailing gear.
Image: Evergreen Line

The grout is manufactured in a batch plant in the Peller Estates work yard and piped to the tunnel boring machine.
Image: Evergreen Line

Grout controls monitor the injection of grout between the TBM liner rings and the earth outside. The grout fills in any gaps between the tunnel and the earth.
Image: Evergreen Line

The tunnel boring machine operator can monitor key information like pressure on the cutter head and TBM progress via the TBM’s control console. They can also steer the TBM left, right, up or down but there is no reverse.
Image: Evergreen Line

Image: Evergreen Line

The cutter head teeth have sensors that communicate directly with the control room when the teeth need to be replaced.
Image: Evergreen Line

The first ring segments will be installed against this thrust frame and then removed once the TBM is fully launched into the hillside.
Image: Evergreen Line

The ring segment conveyer delivers precast ring segments to the ring inserter inside the tunnel boring machine.
Image: Evergreen Line

Precast concrete tunnel liner ring segments.
Image: Evergreen Line

The tunnel boring machine’s trailing gear has a conveyor belt system that expands as the TBM moves forward. The conveyor belt will transport spoils to the tunnel portal for disposal.
Image: Evergreen Line

Featured Image: Evergreen Line