Bridge that Gap: Great Central Railway News

And also with trains able to run at main line speeds?

 

The MLPG was formed before the Nottingham-Rugby section closed! No M6 in those days...

 

I was always of the understanding that the impending construction of the M6, and the height at which they wanted to cross the GC (which is too low for a bridge due tothe already steep gradient heading north on the motorway at that point) was a factor in the closure of the line - or a good excuse.

 

Well fund-raising back in 1969 (Tyseley Open Day) was fairly basic and it was rapidly realised that even getting to Leicester Central station would be too expensive, so the initial Loughborough/ Quorn/Rothley was the only viable option....and that was only just achieved!

 

Just spotted on my Youtube feed that a reunification update video is being premiered tonight at 00:00. An 'interesting' thumbnail picture for it, shall we say;



On the face of it, if that thumbnail is anything to go by, I think it's a logical and sensible solution.
-We know there's a culvert in the way that we need to find a way of bridging - and quite possibly other obstacles that we wouldn't necessarily know about until we put shovels in the ground;
-It avoids needing to source material that satisfies the Venn diagram of 1) appropriate mechanical properties, 2) available in the quantities we would require and 3) be affordable;
-Ease and speed of manufacture and installation, particularly if off-site prefabrication or modern methods of construction are viable options.

 

Isn’t this how it has always been intended to be built? Hence the ‘factory flyover’ appeal.

 

I think that is the bit between the canal and Railway Terrace that was going to be an embankment

John

 

Well the thumbnail sketch shows a loooooonnnngg viaduct, rather than the embankment that's been the idea since 2013/14 ish.

Personally I think going for a viaduct option makes perfect sense.

 

What a great way to start the day! This viaduct makes so much sense! The GCR went on viaducts through Leicester and elsewhere and is a classic image.
It also explains why the engine shed will need to be relocated. To have a single track around the shed and a long section of double track North of the shed (To allow a full length train to wait entry to Loughborough) would mean a double track embankment almost up to Precis-spark. The extra height needed to cross Railway terrace would mean a significantly taller and wider embankment....lots of lorry loads of material!
Using piles and standard bridge decks for the long single track viaduct from the Sewer outflow to the MML bridge will be a lot faster to build, and far less intrusive in terms of lorry movements during construction. It also means though that it becomes one construction project rather than three phases but I suspect because of the modular construction, a smaller workforce could be used?

CAUTION WIMB Alert!
It would also be good if the single track bridge across the sewer outflow had steel lattice parapets ( as per the new Quorn bridges and canal bridge) ....also the viaduct could have blue brick arch facades along the East side where it runs past Precis-spark. This was done on the new MML bridge abutments.
If you really had some spare cash, then a non-structural "Bowstring Girder" would be nice across Railway terrace!

 

Another very professional update and good logical update on the designs.

Looking at the use of the specialist contractors for both the design and building, the preservation movement has come a long way from the early days of scraping pennies together to scrape rust off rolling stock and infrastructure!

I can't think of any active heritage railway projects that are being done on the scale of the GCR gap, since the WHR was completed. Are there any?

 

Hi Chris
I think the Rother Valley Railway extension is the closest to the GCR in scale. The L & B has the potential to be bigger though.

 

Good shout on the Rother Valley and L&B.

 

What makes the 'gap' project unique, I think, is the sheer complexity of the engineering in a relatively short stretch of line. I'm not suggesting the RVR or L&B don't have just as many engineering issues to resolve as I daresay they do, but they'll be stretched out in-between the relatively easy bits.

Nice, elegant solution the 10-span viaduct past Preci-Spark, and CWR to address their concerns over vibration (I understand they do some high-precision engineering and this was an issue). But please @Flying Phil no blue bricks! It's a modern bit of railway and it shouldn't pretend to be anything else.

(I don't see any provision in the plan in the video to add a spur to the tip site...)

 

Is there any indication of the gradient(s) through this site? How does it compare with the ruling grade of 1/176 (10 yds /mile)?
Pat

 

I thought that the tip site had been declared unstable and unfit for any heavy development, ruling out the works. However a smaller running shed(s) on the existing site with the works in other already existing buildings would be logical.

 

It was always known the tip site would need some sort of piling/stabilisation if anything was put there, and that would be expensive. The reason I mentioned it was that when it was announced that the shed would definitely move, the implication seemed to be "all options will be considered". The fact that there isn't so much as a dotted outline on that drawing might indicate that that is one option which is definitely dead; I don't know though, just speculating.

Not sure which "existing buildings" you mean, unless you're talking about moving the overhauls into an industrial unit off-site Swanage-style? (I couldn't see that being a popular option, but stranger things have happened.)

 

I was thinking of buildings north of the gap.

 

Well, handy though those are, they are already full to bursting with things which already live north of the gap. And not big enough to service an 18-mile line. And there is the small matter of the interim period between old-shed-flattening and gap-filling, which could be anything from a few months to a few years depending on quantities of available time/money/optimism/signalling engineers/magic.

 

Broadly a positive announcement I think. It's a slight shame to see just *how* modern the design is and arguably out of keeping with a heritage railway, but totally appreciate that in the real world costs need to be kept down.

I'll certainly chip in another small donation to keep up the momentum!

 

Now it's pretty obvious that 95% of "the gap" will be single track, would it not make sense to squeeze a new shed in to the west of the new line, writing off the double-track over the canal bridge?