The Anonymous Widower

London’s First Two HS2 Tunnelling Machines Ordered

The title of this post, is the same as that of this article on Ian Visits.

The title gives a description of the story, but the article reveals a lot of details about the tunnels for High Speed Two.

  • There will be ten tunnel boring machines (TBMs) in total for High Speed Two.
  • The main tunnels are 42 % larger than those for Crossrail.
  • There will be three pairs of tunnels under London; West Ruislip and Greenford (5 miles), Greenford and Old Oak Common (3.4 miles) and Old Oak Common and Euston (4.5 miles).
  • It looks like these first two machines will bore the two outer tunnels and that two extra TBMs will be ordered for Greenford and Old Oak Common.

There are also two excellent infographics.

  • The first shows the route of the tunnels.
  • The second shows the three pairs of tunnels and the directions, they will be bored.
  • The third also  discloses that the tunnels will be up to fifty metres deep.

There will also be a vent shaft at Greenford in Green Park Way, when the tunnel opens.

This Google Map shows the area.

Note.

  1. The A 4127 runs North-South across the map.
  2. The railways running across the map are Acton and Northolt Line and the Central Line, which serves Greenford station.
  3. The Greenford Branch Line goes South from a triangular junction.

The green site squeezed in between the industrial buildings and just to the North of the railways could be the site for the vent shaft.

This second map is a clip of High Speed Two’s map of the area.

The black line is the route of the High Speed Two tunnel.

  • It is to the North of the Central Line.
  • It looks to be close to the vacant site.

When High Speed One was built through Hackney, they bored the tunnels under the North London Line, so High Speed Two only seem to be repeating, what worked successfully.

These pictures show some of the ventilation shafts for High Speed One in East London.

Crossrail’s vent shafts are smaller in number and less obtrusive. There is one disguised in this building; Moor House.

I would hope that High Speed Two could improve further and create a useful building on top, that adds value to the area and doesn’t follow the utilitarian constructions of High Speed One.

Boring the Tunnels

According to the infographics, the three tunnels will be built in the following directions.

  • West Ruislip and Green Park Way – Towards Green Park Way
  • Green Park Way and Old Oak Common – Towards Green Park Way
  • Old Oak Way and Euston – Towards Euston.

These High Speed Two tunnels will be the fourth set of large tunnels to be bored under London in recent years after High Speed One, Crossrail and the Thames Tideway Scheme and I suspect there will be those , who will have worked on all four, at every level.

  • I wouldn’t be surprised to see some innovative use of the TBMs, so that they are reused if possible.
  • As four TBMs start at Old Oak Common and four finish at Green Park Way, I wonder if the planners have sequenced the insertion and extraction of the TBMs to make best use of the very expensive cranes needed.
  • Two TBMs will be inserted at West Ruislip, where there is a public golf course that must give plenty of space.
  • Two TBMs will be extracted a short distance to the North of Euston station. Again, there appears to be space.

I suspect experience from previous projects and good project planning has contributed to the design.

The Work Has Started At Green Park Way 

These pictures show the Greenford site on the 12th of October 2020.

These pictures were taken from a Central Line train.

The Tunnel Portal Works At West Ruislip Station

These pictures show the West Ruislip site on the 12th of October 2020.

Note.

  1. This is where High Speed Two will emerge from the tunnels from Euston.
  2. The first three pictures were taken from the bridge over the railway and show the Chiltern Main Line, Chiltern’s turnback siding and the High Speed Two site.
  3. There is no sign of works around the car park and the L-shaped care home on the station side of the road, so I would assume, that they will be unaffected by the tunnel.

This Google Map shows West Ruislip station.

Note.

  1. The Central Line terminating in West Ruislip station.
  2. The Chiltern Main Line passing through the station.
  3. The scar of the construction of High Speed Two alongside the Chiltern Main Line.

If you follow the Chiltern Main Line on Google Maps for a couple of miles, you can see the route of High Speed Two.

This second map is a clip of High Speed Two’s map of the area.

Note.

  1. The black line is the High Speed Two tunnel, that surfaces, where it changes colour.
  2. The L-shaped care home is still on the map, so it does appear the tunnel goes underneath.

It looks to me, that the bridge and Chiltern Trains going towards London, will offer good views of the tunnel works.

In the late 1950s, British Rail were increasing the number of tracks through Hadley Wood station, from two to four, by digging two extra tunnels.

I can remember my father taking me to see the works from Waggon Road or Wagon Road, which had and still had a few years ago, different names at either end.

 

 

October 10, 2020 - Posted by | Transport | , , , ,

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