City Loop tunnels - detailed plans??

 
  trestle_nutter Train Controller

Location: Yarra Valley
I thought this topic would have been covered before but I can't find anything by doing a search.

Are there detailed plans of the City Loop tunnels including  number of tunnels, different levels, portals etc, available on line any where (not just the schematic plan that just shows it as a symetrical loop)?

Why I ask is that recently on an afternoon Lilydale train (heading clockwise around the loop) I noticed through the glass door into the forward carriage that we were turning towards the left (I think between Flagstaff & Melb. Central).

I would have thought that apart from the curves at the four corners of CBD, the tunnels would be straight between the stations.

Would there be any photos (say from a drivers cabin) that would show this curve?

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  alstom_888m Chief Commissioner

Location:
There are a few cab view videos on YouTube.
  tranzitjim Chief Commissioner

Location: Banned
I guess that such plans would be 'less open' as they would be concerned with terrorists wanting to do damage to it.
  wongm GEEWONG

Location: Geelong, Victoria
Are there detailed plans of the City Loop tunnels including  number of tunnels, different levels, portals etc, available on line any where (not just the schematic plan that just shows it as a symetrical loop)?
"trestle_nutter"

I'd try the State Library of Victoria - I recall that they hold a lot of CIty Loop related material in their maps section. I believe you need to visit someone there to get it, you can't make requests online like the rest of the book collection.

This pamphlet - 'City Loop : geographical layout' might be of interest:
http://search.slv.vic.gov.au/primo_library/libweb/action/dlDisplay.do?vid=MAIN&reset_config=true&docId=SLV_VOYAGER945774




  wongm GEEWONG

Location: Geelong, Victoria
Why I ask is that recently on an afternoon Lilydale train (heading clockwise around the loop) I noticed through the glass door into the forward carriage that we were turning towards the left (I think between Flagstaff & Melb. Central).

I would have thought that apart from the curves at the four corners of CBD, the tunnels would be straight between the stations.

Would there be any photos (say from a drivers cabin) that would show this curve?
"trestle_nutter"

The reason for the kink between Melbourne Central and Flagstaff is due to the different platform widths.

Melbourne Central was built in a cut and cover box, so it needed to fit inside the width of Latrobe Street, plus any of the south side of the street where the shopping centre is now. For that reason they chose an island platform configuration.

For Flagstaff station they couldn't dig do that - the cut would need to be much deeper - so chose to build two separate 'stacks' of side platforms, with bored tunnel linking them. If they squished the two side by side platform tunnel 'stacks' beside each other, presumably the rock in between them would not be strong enough to hold up the ground above.

The end result of the two station designs track centres that were different widths. The south track (Northern Loop) was kept straight, with the north track (Burnley Loop) being kinked.

This is looking east along the Northern Loop from Flagstaff downhill towards Melbourne Central: I'll have to take a photo tomorrow showing the kink from the Burnley Loop platform.

[img]http://railgallery.wongm.com/cache/city-loop/E105_5457_595.jpg[/img]



  wongm GEEWONG

Location: Geelong, Victoria
Are there detailed plans of the City Loop tunnels including  number of tunnels, different levels, portals etc, available on line any where (not just the schematic plan that just shows it as a symetrical loop)?
"trestle_nutter"

Another source to try out are articles from academic journals - unfortunately if you aren't a uni student, or can get one to log into their uni library for you, you'll have to pay $$$ to get access to them.

One article I did find for free was this paper 'Mixed Face Tunneling on Melbourne Underground' by Alfred M. Petrofsky (of Jacobs Associates) in the September 1980 'Journal of the Construction Division':
http://www.jacobssf.com/index.php/publications/article_view/462/

The full PDF is here, which details with the construction of the Spencer Street Yard to Flagstaff Station bored tunnels. There are some nice diagrams as well:
http://www.jacobssf.com/images/uploads/1980_Petrofsky_Mixed_Face_Tunneling_Melbourne.pdf
  wongm GEEWONG

Location: Geelong, Victoria
I've found another journal article, this time the part of note is a geological profile of the tunnel route, which also happens to show the depth of the tunnels in relation to the surface.

'Pilot Tunnel lnvestigations into Aspects of Excavation and Primary Support for Melbourne Underground Rail Loop Tunnels' from the 1974 Australian Tunnelling Society (ATS) Conference Proceedings:
http://www.jacobssf.com/index.php/publications/article_view/465/

The PDF is here:
http://www.jacobssf.com/images/uploads/1974_Neyland_Melbourne_Underground_Rail_Loop.pdf
  trestle_nutter Train Controller

Location: Yarra Valley
Thanks wongm, a wealth of info & knowledge as always

cheers
  jakar Assistant Commissioner

Location: Melbourne
Looking through the links that wongm posted, i see that there is a draft relief tunnel/shaft just west of Flagstaff station. Google maps street view shows a low level concrete structure just off Latrobe St in the Flagstaff gardens. Is this the top of the shaft? Was there only one draft relief tunnel/shaft on the Melbourne Underground?

Thanks, Jakar
  Revenue Chief Commissioner

Yes, the low concrete structure in Flagstaff gardens is one of the vents.
There are a few across the network.

The notes from the Tunnelling Conference are the best resources available. There was actually a whole lot of papers in the booklet of conference papers. Really good resource.
  wongm GEEWONG

Location: Geelong, Victoria
Yes, the low concrete structure in Flagstaff gardens is one of the vents.
"Revenue"

And a photo:

[img]http://railgallery.wongm.com/cache/city-loop/E110_2000_595.jpg[/img]

The welded mesh grill on the top keeps most of the crap out, when you look down there isn't much to see (the shaft makes a few turns before it reaches the running tunnels)

[img]http://railgallery.wongm.com/cache/city-loop/E110_2003_595.jpg[/img]

There are a few across the network.
"Revenue"

I believe there there are draught relief structures at the each end of each station: the easiest one to see is at the very western end of Melbourne Central platform 3, where you can see daylight behind a wall of welded mesh.

The others cross passages are only visible if you press your nose right up against the train window when arriving or departing from stations. Some appear to be open to the running lines, while others have full height fences blocking access.
  alstom_888m Chief Commissioner

Location:
Oh so that's what that thing is.

Yeah I can see daylight at the grate at the end of platform 3 at Melbourne Central. Where does that surface?
  jakar Assistant Commissioner

Location: Melbourne
Thank you Revenue and wongm for your replies.

It's been quite a while since i've been on a platform in the loop, but I always remember feeling quite a strong breeze before a train appeared which makes me wonder what it would be like without these draft relief shafts. On the off chance that either of you have done this, but if you stand on top of the shaft is there any noticeable breeze coming from it?

Cheers,

Jakar
  Morbo Locomotive Driver

(Apols if this has been answered before; can't do search on the mobile interface)


The green emergency signs in the loops that were put in a few years ago point to the nearest emergency exit. Between Richmond and Parliament on the Caulfield Loop there appears to be one midway (I've never been on a train going slow enough to see it though). Are these just cross tunnels to the other loops, or are they stairs to the surface? If so, where do they come out? Are there others between the other underground stations?
  wongm GEEWONG

Location: Geelong, Victoria
(Apols if this has been answered before; can't do search on the mobile interface) The green emergency signs in the loops that were put in a few years ago point to the nearest emergency exit. Between Richmond and Parliament on the Caulfield Loop there appears to be one midway (I've never been on a train going slow enough to see it though). Are these just cross tunnels to the other loops, or are they stairs to the surface? If so, where do they come out? Are there others between the other underground stations?
"Morbo"

I believe there are only two 'real' mid-tunnel emergency exits, one in the Caulfield Loop between Parliament and Richmond, the other in the Northern Loop between North Melbourne and Flagstaff. Here is the emergency exit signage showing the distance to the latter exit, presumably all other 'real' emergency exits will be marked on the mid-tunnel signage in the same way.
[img]http://railgallery.wongm.com/cache/city-loop/E115_0743_595.jpg[/img]

The Northern Loop exit can be seen from slowly passing trains, with a brightly lit set of concrete stairs, not a ladder or other 'maintenance only' type access. The cross passages are much harder to spot, as there isn't as many lights in them. I'm guessing the higher level of lighting at the exit stairs is to meet evacuation route requirements.

Last year there was a news article in The Age about safety issues in the City Loop, including supposedly locked emergency exits:
http://www.theage.com.au/victoria/city-loop-safety-fears-20110921-1klbd.html

I am theorising that the 'locked exits' mentioned in the Age article are the ventilation shafts and cross passages, as these have a reason to be closed to pedestrian access (not designed to meet evacuation standards) while the proper exit stairs have one way doors and alarm systems to prevent unauthorised access, a standard feature of fire escapes anywhere else in Australia.
  wongm GEEWONG

Location: Geelong, Victoria
And on a slight tangent, a drivers view of the underground junctions by Rod Williams (former suburban train driver)

City Circle Loop, left to Jolimont, right to Flinders Street



Caulfield Loop heading towards Richmond



Northern Loop heading towards North Melbourne

  Braddo Deputy Commissioner

Location: Narre Warren
Those pictures are great. I'm surprised to see graffiti though, why bother tagging something people can't see?
  sparkdriver Assistant Commissioner

Location: Melbourne
Those pictures are great. I'm surprised to see graffiti though, why bother tagging something people can't see?
"Braddo"


There's graffiti inside all the loop tunnel entrances and has been for years. Some go in a few hundred metres.
  LamontCranston Chief Commissioner

How do they manage to not get hit??
  wongm GEEWONG

Location: Geelong, Victoria
How do they manage to not get hit??
"LamontCranston"

Presumably by only visiting after the last train has run.

There are also refuge alcoves at regular intervals if something did come along - given you are in a confined tunnel you will hear the train coming from a mile away.
  Foamer GEEWONG

Location: Geelong
How do they manage to not get hit??
"LamontCranston"

Presumably by only visiting after the last train has run.

There are also refuge alcoves at regular intervals if something did come along - given you are in a confined tunnel you will hear the train coming from a mile away.
"wongm"


Not posting from experience I hope.....
Is there a topic that you do not know about or have at least a photo on?  I am amazed every time!  Keep it up.
  wongm GEEWONG

Location: Geelong, Victoria
Not posting from experience I hope.....
"Foamer"

Just by paying a lot of attention when I pass through by train. Smile

As for the illuminated exit signs, they were added in 2006 as part of a general safety and security upgrade. The older ones were painted on the tunnel walls: black text on yellow.
http://www.railpage.com.au/f-t11321261.htm
  OzFrog Locomotive Driver

Location: Melbourne
Just had a look at the first link of papers that wongm referred to, and I noticed that one of the maps shows the Northern Loop access shaft starting just northwest of the Adderley/Latrobe intersection. Would this be where the changeover from bored to cut/cover would have occurred for the Northern Loop?

I ask because I have thought that cut/cover section to be at least a few hundred metres long in the times I have travelled through it, and would be curious to know if they actually had to extend the cut/cover underneath Dudley St (that would have been some engineering feat if so, considering that the railway bridge also sits on top of Dudley directly over the tunnels).
  Turbo Thomas Assistant Commissioner

Location: Melbourne
A couple of things I've heard about the City Loop but have never been able to verify.

- there was supposed to a short tunnel under Spring St that connected the Northern Loop to the Caulfield Loop, this would provide a route that could by-pass Flnders St if needed.

- when the loop was completed, they decided that the best thing to do with some of the digging machinery was to bury it done there, it would have cost more to try and remove it.

- Spencer St No.1 Signal Box had to be slightly moved due to the loop tunnels directly underneath it.

- there are fans in the loop that can either blow or suck air, so that the direction of air in the loop can be controlled in case of a fire.

Can anyone confirm these things ?
  wongm GEEWONG

Location: Geelong, Victoria
there was supposed to a short tunnel under Spring St that connected the Northern Loop to the Caulfield Loop, this would provide a route that could by-pass Flnders St if needed.
"Turbo Thomas"

Said connection isn't show in any of the early plans for the City Loop.

However, of you go back far enough you will find a number of other layouts, such as this one:
http://www.railpage.com.au/f-p712747.htm



when the loop was completed, they decided that the best thing to do with some of the digging machinery was to bury it done there, it would have cost more to try and remove it.
"Turbo Thomas"

It is not unknown for a tunnel boring machine (TBM) to get abandoned underground:
http://www.ats.org.au/index.php?option=com_content&task=view&id=390&Itemid=8

From what I have read the City Loop tunnels were dug using a mix of tunnel boring machines and roadheaders. I'm not sure what happened to the equipment once the job was done.

Spencer St No.1 Signal Box had to be slightly moved due to the loop tunnels directly underneath it.
"Turbo Thomas"

I've see photos online showing a big chunk of the Spencer Street carriage yards covered with temporary decking, as the cut and cover work went on underground. I think the signal box only required underpinning, not relocation?

there are fans in the loop that can either blow or suck air, so that the direction of air in the loop can be controlled in case of a fire.
"Turbo Thomas"

Ventilation fans are mentioned here:
http://www.theage.com.au/victoria/call-for-funds-to-fix-loops-problems-20111219-1p2kd.html

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