Jump to content
 

Recommended Posts

What was interesting about the cross-tunnel film was the unstated amount of destruction of cast concrete rings and the requirement for bespoke replacements. 

Since the cross-tunnel links two completed running tunnels which are lined with arc slabs as part of their build, any oblique connection has to destroy part of the supporting rings of both tunnels. Since these rings support the tunnels, how do they do that?

  • Agree 1
Link to post
Share on other sites

57 minutes ago, Arun Sharma said:

What was interesting about the cross-tunnel film was the unstated amount of destruction of cast concrete rings and the requirement for bespoke replacements. 

Since the cross-tunnel links two completed running tunnels which are lined with arc slabs as part of their build, any oblique connection has to destroy part of the supporting rings of both tunnels. Since these rings support the tunnels, how do they do that?

I wondered about that.

do they put a different ring in every 500 metres?

  • Interesting/Thought-provoking 1
Link to post
Share on other sites

51 minutes ago, Arun Sharma said:

What was interesting about the cross-tunnel film was the unstated amount of destruction of cast concrete rings and the requirement for bespoke replacements. 

Since the cross-tunnel links two completed running tunnels which are lined with arc slabs as part of their build, any oblique connection has to destroy part of the supporting rings of both tunnels. Since these rings support the tunnels, how do they do that?

 

From earlier photos, they use a precision drilling rig to cut a hole through the tunnel rings and then constructed a heavy duty, reinforced cross tunnel portal, through which the cross tunnelling could begin.

 

1644851925297-png.2783650

 

 

 

Here are some photos from the press release, that accompanied the YouTube video.....

 

c98af0556a704578be0b2415c8ac5840.jpeg?wi

 

f9dc075e55e04bd49b3f1de0bb5cc391.jpeg?wi

 

39934c3dd19140dbafc32e1f89e890a2.jpeg?wi

 

 

  • Like 2
  • Thanks 1
  • Informative/Useful 3
Link to post
Share on other sites

Also in the Chilterns Tunnels....

 

Today's update.

Florence over 6km in with 10km remaining.

Cecilia is running about 300 metres behind.

 

The half way point should be reached later this year.

( note:  Xmas is only 4 months away)

 

 

.

  • Like 3
  • Informative/Useful 1
Link to post
Share on other sites

More HS2 tunnelling.....

 

Reported on the SkyScraper City forum.

Both TBM's at the West Ruislip portal are now fully assembled and being prepared to start digging east, towards Greenford.

The first is due to be switched on next week (Tues or Weds) and will cut one metre into the concrete wall, as part of the preparatory work, before being launched.

 

 

.

Edited by Ron Ron Ron
  • Like 1
  • Thanks 1
  • Informative/Useful 2
  • Interesting/Thought-provoking 1
Link to post
Share on other sites

  • RMweb Premium
7 hours ago, Ron Ron Ron said:

More HS2 tunnelling.....

 

Reported on the SkyScraper City forum.

Both TBM's at the West Ruislip portal are now fully assembled and being prepared to start digging east, towards Greenford.

The first is due to be switched on next week (Tues or Weds) and will cut one metre into the concrete wall, as part of the preparatory work, before being launched.

 

 

.

I better rerig my spreadsheet once I know the names.

 

Jamie

Edited by jamie92208
Link to post
Share on other sites

AIUI the concrete rings for the Ruislip-Greenford tunnels are coming from or via Grain. So there is one train per day on that  route each way.

 

Spoil from the tunnelling is initially being stored on site/processed before being removed later by rail.

 

Rings for the Thames Sewer that came via Grain but I believe originated from Lincolnshire, is it the same for these HS2 rings. 
 

It is surprising that the Rings are not coming from the plant at the southern portal of the Chiltern Tunnels which is only a few miles away, particularly as the Chiltern Tunnels are almost complete as far as tunnelling is concerned.

  • Like 2
  • Agree 1
Link to post
Share on other sites

  • RMweb Premium
5 minutes ago, Bob83a said:

AIUI the concrete rings for the Ruislip-Greenford tunnels are coming from or via Grain. So there is one train per day on that  route each way.

 

Spoil from the tunnelling is initially being stored on site/processed before being removed later by rail.

 

Rings for the Thames Sewer that came via Grain but I believe originated from Lincolnshire, is it the same for these HS2 rings. 
 

It is surprising that the Rings are not coming from the plant at the southern portal of the Chiltern Tunnels which is only a few miles away, particularly as the Chiltern Tunnels are almost complete as far as tunnelling is concerned.

I don't think there is enough capacity at the Chiltern portal site, they have over a year of tunnelling to go and also the segments for the Colne Valley viaduct.  I wonder if the facility at Grain is the same one that did the segments for the Channel Tunnel.

 

Jamie

  • Like 1
  • Agree 1
Link to post
Share on other sites

2 hours ago, jamie92208 said:

I don't think there is enough capacity at the Chiltern portal site, they have over a year of tunnelling to go and also the segments for the Colne Valley viaduct.  I wonder if the facility at Grain is the same one that did the segments for the Channel Tunnel.

 

Jamie

I believe it is.

  • Thanks 1
Link to post
Share on other sites

  • RMweb Premium
7 hours ago, Bob83a said:

AIUI the concrete rings for the Ruislip-Greenford tunnels are coming from or via Grain. So there is one train per day on that  route each way.

 

Spoil from the tunnelling is initially being stored on site/processed before being removed later by rail.

 

Rings for the Thames Sewer that came via Grain but I believe originated from Lincolnshire, is it the same for these HS2 rings. 
 

It is surprising that the Rings are not coming from the plant at the southern portal of the Chiltern Tunnels which is only a few miles away, particularly as the Chiltern Tunnels are almost complete as far as tunnelling is concerned.

The sewer rings came from Tallington.

  • Agree 1
  • Informative/Useful 1
Link to post
Share on other sites

This morning drove up from Stoke Manderville village towards P Risboro  past the part were line crosses road  ,I was astounded to see the trackbed going towards Wendover is now ready for the next stage to be started .It now is leveled with shoulders and looks great. 

  • Like 1
  • Informative/Useful 3
  • Interesting/Thought-provoking 2
Link to post
Share on other sites

Meanwhile, in London.

The Victoria Rd site, just to the west of OOC.

At this location, a large crossover box is being built on the approach to the OOC station.

Alongside this, there's an associated ventilation and access shaft.

 

Here is a view from the bottom of the shaft, showing a linking tunnel to what will be the underground crossover box.

 

 

1661583363812-png.3725346

 

 

 

.

  • Like 8
Link to post
Share on other sites

  • RMweb Premium
27 minutes ago, Ron Ron Ron said:

Tunnelling.

 

A bit of light reading, with some nice diagrams and illustrations.......

 

https://learninglegacy.hs2.org.uk/document/shallow-tbm-launch-of-the-northolt-tunnel-west-tbms-at-west-ruislip-hs2-lot-s2/

 

 

 

.

 

The link only takes you back to the top of this page  unfortunately.

 This might work

https://learninglegacy.hs2.org.uk/document/shallow-tbm-launch-of-the-northolt-tunnel-west-tbms-at-west-ruislip-hs2-lot-s2/

 

Jamie

  • Agree 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...