Tunnel dimensions

[Socimi]

I'm looking for the dimensions of these type of squared double-track tunnels:

 

 

Does someone have a technical drawing or knows where to find one?

[bill937ca]

The loading gauge and track center could be an alternative.

[Sheffie]

I’d measure the tunnel in the photo and the train height or width (whose dimensions should be easily found) and estimate it from there. 

[ben_issacs]

Socimi,

Scaling from your photo, using the track width at the left (yes, I know it's curved, but it will do as a marker), I make the tunnel width 8.06m (26 1/2 feet) and height 5.3m (!7 1/2 feet).

Didn't do the rail height, but this could be say 200mm (8 inches)

These dimensions probably correct to +/- 100mm.

Regards, 

Bill, 

Melbourne.

 

 

[ben_issacs]

Socimi,

If you divide the full size dimensions that I worked out by 150, you get 35.5mm for the height and 53.7mm for the width in N scale, which you're probably wanting.

Regards, 

Bill 

Melbourne

 

[gavino200]

On 8/9/2019 at 1:29 PM, Socimi said:

I'm looking for the dimensions of these type of squared double-track tunnels:

 

 

Does someone have a technical drawing or knows where to find one?

 

I'm curious if you built this tunnel? 

 

Did you use 35mm as the height? Or did you add some wiggle room? 35mm looks awfully close to the height of the pantograf. 

 

By any chance do you have the name or location of this tunnel. In the picture it looks like the tunnel continues inside at the same height as the opening. Any idea if this is the case?

[Socimi]

6 hours ago, gavino200 said:

 

I'm curious if you built this tunnel? 

 

Did you use 35mm as the height? Or did you add some wiggle room? 35mm looks awfully close to the height of the pantograf. 

 

By any chance do you have the name or location of this tunnel. In the picture it looks like the tunnel continues inside at the same height as the opening. Any idea if this is the case?

 

I needed the dimensions of the tunnel not for a model railway, but rather for a route i was making in Trainz Simulator.

 

It's the lefternmost of the two portals on the extreme eastern end of the Nagoya Subway Tsurumai Line (the route i was going to make), located a few meters after Akaike station, the easternmost terminus. Indeed they're pre-cast concrete structures for shallow-level tunnels, so the height (and other dimensions) of the portal are exactly the same as in the rest of the tunnel.

About the project itself, it's in an "hiatus" status: the trackage is actually pretty much completed and done, but i got stuck while making the scenery and underground stations. I also started working on the rolling stock (namely the 3000 Series, the 3050 Series and the Meitetsu 100 Series), but left them unfinished at various stages of "uncompleteness".

As i said, the project is currently suspended, but it might re-start sooner or later as i'm getting the help of a friend on the Trainz forum for the tricky parts.

 

[gavino200]

8 minutes ago, Socimi said:

 

I needed the dimensions of the tunnel not for a model railway, but rather for a route i was making in Trainz Simulator.

 

It's the lefternmost of the two portals on the extreme eastern end of the Nagoya Subway Tsurumai Line (the route i was going to make), located a few meters after Akaike station, the easternmost terminus. Indeed they're pre-cast concrete structures for shallow-level tunnels, so the height (and other dimensions) of the portal are exactly the same as in the rest of the tunnel.

About the project itself, it's in an "hiatus" status: the trackage is actually pretty much completed and done, but i got stuck while making the scenery and underground stations. I also started working on the rolling stock (namely the 3000 Series, the 3050 Series and the Meitetsu 100 Series), but left them unfinished at various stages of "uncompleteness".

As i said, the project is currently suspended, but it might re-start sooner or later as i'm getting the help of a friend on the Trainz forum for the tricky parts.

 

 

Thanks Socimi. I think this is exactly the kind of tunnel I'm looking for. Low ceiling and flat walls. I'll look around at other tunnel designs but I really thing this fits the bill. I'm going to make a mock up for planning purposes. The actual tunnel I won't get to for a while. Would you mind if I posted about my progress in this thread? Or would you rather I start my own?

[Socimi]

Yes, post here as you please.

Ah, by the way, i may have a Sketchup-made 3D model of the tunnel in question, i can post it here if you need it.

(mesaurments might not be 100% accurate)

[gavino200]

Thanks. Sure it wouldn't hurt to see it. I'll probably go with the proportions from the photo. I'm going to visit an art supply store today to get some cardstock to make a mock up. 

[Socimi]

Here it is.

 

I did actually made the tunnel with the above photo as reference, and using the model of the Nagoya Subway 3000 Series (the train in the picture) i did earlier with the correct dimensions as base for proportions; altough with this method, it works correctly only if the train front is exactly aligned with the portal of the tunnel, wich i fear this is not the case.

That's why in the opening post i asked if somebody had the dimensions, or even better, had or knew where to get a proper technical drawing.

 

Anyway, i remember distinctively that even with the possibly-wrong proprtions, trains fitted the tunnel well.

(pantographs a bit less though).

Edited December 10, 2020 by Socimi

[gavino200]

Thanks. I sent an request to access the link. 

 

I'm going to mostly run subway/commuter trains through this tunnel, but I want to be able to also run all my trains through it. I'm guessing I'll probably have to oversize it a bit. The width to accommodate longer cars on curves, and the height to accommodate all pentagraphs. I have a few German trains that can sometimes have giant penagraphs. Those will probably be the biggest problem. 

 

Keeping the height to the minimum is my main concern. I'd like to roughly approximate the form of a real tunnel rather than copy it exactly. My main goal right now is to find out how high the tunnel needs to be so I can carry on planning my layout. Building the tunnel will come later. 

 

I also need to think about how much space/concrete to have between the subway tunnel roof and a track/station above. I bought a railfan magazine today dealing with bridge and tunnel construction. It has some interesting tunnel construction pictures. It looks like the distance can be quite small. Smaller is better for my purposes. I'm wondering if @Kiha66 or another engineer can give some input on this. I know that in NYC subway lines under the street are really just a few feet below. How about a subway running under a railway line? I don't mind going a bit shallower than prototypical, but I'd rather not make it too far-fetched either. 

[gavino200]

On 12/9/2020 at 5:21 PM, Socimi said:

 

 

 

It's the lefternmost of the two portals on the extreme eastern end of the Nagoya Subway Tsurumai Line (the route i was going to make), located a few meters after Akaike station, the easternmost terminus. Indeed they're pre-cast concrete structures for shallow-level tunnels, so the height (and other dimensions) of the portal are exactly the same as in the rest of the tunnel.

 

 

 

In this google earth view it looks like the subway is very shallow. I couldn't find a picture showing the depth of concrete between the tunnel entrance in the picture and the ground level above. Have you seen any by any chance.

 

it looks like many of the simple subway platforms would also be relatively easy to model. 

 

https://www.google.com/url?sa=i&url=https%3A%2F%2Fcommons.wikimedia.org%2Fwiki%2FFile%3ATokyo_Metro_Sendaki_sta_001.jpg&psig=AOvVaw2LdhRE73Plzyim9VE6PI0s&ust=1607727267156000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCPj67fXBxO0CFQAAAAAdAAAAABAD

[gavino200]

A few height measurements. Ben's calculations are based on the track with in the photo. Using a 1:150 scale he gets a model height and width of 35.5mm and 53.6mm.  Using a scale of 1:160 the height and width are 33 mm and 54mm

 

I agree it would be good to fine accurate measurements. I'll need to check Ben's work. Also there might be some underestimate due to parallax and perspective ad he's measuring the with of rails in picture left while the photographer is standing in front of the train. Train width might be a better measurement to use if it's known. 

 

The height line in the picture starts at gravel/ballast height. My measurements for tunnel construction will be from the baseboard on which (in my case) Kato Unitrack will sit. 

The plastic base of Kato unitrack is 5mm high.

Therefore I'll add 5mm to the height measurement given above (same for both scales)

I'm going to use the 1:50 scale and add 5mm of height

 

This gives me model dimensions of Width of 53.6 mm and a height of 40.5 mm

For me there needs to be some space between the roof top and the pantograph to place modelled catenary fixtures. 

 

Now some pantograph measurements. I measure height from the "baseboard" to the top of the pantographs. Btw I subtraced 2 mm from each measurement for the small part at the bottom of the ruler before the scale starts. \

 

Btw, I took the measurements first with two hands, then "staged" the measurement for the photo. You'll notice a bit of sloppiness. 

 

First an E231 - most likely what I'll run on this line. 

 

39 mm - too high 

 

 

Fleishmann loco with pantograph geared down to normal angles. 

 

41 - too high

 

 

Fleishmann loco with old style panto - I haven't tried to gear this down but I'm sure I'll be able to.

 

43 mm - too high

 

 

A Fleischmann panto straight out of the box without gearing. This is about as high as a panto can ever get.

 

47 mm - way to high. But really this is an outlier. I would never run a train like this. It looks horrible. 

IIRC if you run a Fleishmann loco with the panto in this position it doesn't clear the regular Kato catenaries 

 

 

 

For now I'll use either the 43mm or 47 mm as the pantograph height to clear.

I'll add another 6mm for rooftop details and small catenary fixtures. 

 

So  for the first mockup: Height either 49 mm or 53 mm 

 

The with of a Kato double track straight is 58mm. So Ben's 53.6 will have to be increased. 

To clear long cars on turns it will also have to be increased but I can't tell how much without testing.

I'm going to give it an extra 5mm on each side. 

 

So for the first mockup : Width 68 mm

Edited December 11, 2020 by gavino200

[Socimi]

10 hours ago, gavino200 said:

Thanks. I sent an request to access the link. 

 

I also need to think about how much space/concrete to have between the subway tunnel roof and a track/station above. I bought a railfan magazine today dealing with bridge and tunnel construction. It has some interesting tunnel construction pictures. It looks like the distance can be quite small. Smaller is better for my purposes. I'm wondering if @Kiha66 or another engineer can give some input on this. I know that in NYC subway lines under the street are really just a few feet below. How about a subway running under a railway line? I don't mind going a bit shallower than prototypical, but I'd rather not make it too far-fetched either. 

 

Well, taking a look from my Trainz route, these are the station depths from street level:

 

T01 Kami-Otai  +7.5m (elevated station)
T02 Shonai-Ryokuchi-Koen  -18m

T03 Shonai-Dori -17m

T04 Joshin -20m

T05 Sengen-Cho -20m

T06 Maronouchi - 18m (Sakuradori Line platforms below)

T07 Fushimi -17m (Higashiyama Line platforms above)

T08 Osu-Kannon -17m

T09 Kamimaezu -18m (Meijo and Meiko Lines platforms above)

T10 Tsurumai -13m (JR Central Chuo Line above on elevated tracks)

T11 Arahata -15m

T12 Gokiso -14m (Sakuradori Line platforms below)

T13 Kawana -14m

T14 Irinaka -13m

T15 Yagoto -14m (Meijo Line platforms below)

T16 Shiogamaguchi -16m

T17 Ueda -12m

T18 Hara -14m

T19 Hirabari -10m

T20 Akaike -8.80m

 

I'm sure there are more shallow lines than the Tsurumai Line, but in general, try to have atleast 3 to 5 scale meters between the top of the tunnel and the track above.

[gavino200]

I made a rough mockup out of cardstock today. I used a different thickness of above tunnel concrete on each end. The thin side is 3 scale meters. The thick side is just less than 5 scale meters. I like how the thinside looks best. But both fit with ease under my height constraint. 

 

 

3 meter above roof thickness

 

 

5 meter above roof thickness

 

 

Good Japanese train pantograph clearance 

 

 

Good German pantograph clearance.

 

 

 

Edited December 11, 2020 by gavino200

[Kiha66]

Nice work gavin! 

 

With modeling you really don't need much vertical space between train lines, a foot thick beam in real life becomes less than two mm in N gauge.  In the prototype some subway lines share walls with the basements of buildings.  A street will usually have at least a few feet of clearance from the tunnel roof to the surface for the road to have proper subroadbed and such, but can be very shallow.  If the line runs under buildings it should have enough clearance to allow the building to have proper foundations, but the inch or two you've given here looks great.