Great Western Main Line electrification - ongoing discussion

[whole diary]

[BerkshireBugsy]

Whilst I admire your optimism, on the 2 bits of line I travel fairly frequently (PAD^» (Paddington (London) - next trains)-RDG^‡(resolve), and RDG-THA on the B&H^▸ (Berks and Hants - railway line from Reading to Taunton via Westbury)) there still seem to be several stretches where there aren't even piles in the ground yet.

For example, around Slough Station, there seems to be very little evidence of electrification work under way at all?

I'm not sure I agree TC^‡(resolve) - there seemed to be quite a few changes around the Twyford/maidenhead section since I last travelled through

[TaplowGreen]

They've been busy around Burnham/Taplow alright, banging away all night! (so to speak)

To be fair we all had letters from NR^» (Network Rail - home page) explaining what would be happening, when, and apologising for the noise, and also visits from their (very pleasant) representatives.

[TonyK]

On my way out of BRI^» (Bristol Temple Meads - next trains) this morning, I noticed the pile of, er, piles by the siding behind Avonmeads had been substantially augmented.

[Thatcham Crossing]

there seemed to be quite a few changes around the Twyford/maidenhead section since I last travelled through

That's my point really BB, it seems quite sporadic - although I do appreciate they can't be working everywhere at once.

What does seem apparent to me though is that they seem to be leaving the complex/hard bits till last, eg, around some stations, bridges, and areas where there are obstructions close to the track. An example of this is just west of Aldermaston where the boundary of a housing estate (fences/trees/walls) is very close to the line. No sign of any piling, although there is plenty on the rest of that stretch towards Midgham.

[Visoflex]

Anyway back to the original topic In some sections there are just the circular tubes waiting to be cut to size where in other areas there are masts, cross masts and dangly sections (excuse my ignorance on what they are called S&T^▸ (Signalling and Telegraph)!)

The "dangly bits" are referred to as "small part steel".  Also, the perceived lack of progress around stations can be partly explained by the fact that the wires will be held up by different types of support.  The most likely type will be a twin track portal arrangement, and that installing this will need fairly major holes to be cut into station canopies and twin track possessions.  Also, there is a gauge clearance exercise to be done too.  The route will be re-gauged to allow W10 and W12 freight wagons to come through, and also to provide adequate clearance for pantographs in accordance with European inter-operability requirements.  This means a measuring and cutting back of the canopies, where the originals are staying, or a rebuild.

[BerkshireBugsy]

Anyway back to the original topic In some sections there are just the circular tubes waiting to be cut to size where in other areas there are masts, cross masts and dangly sections (excuse my ignorance on what they are called S&T^▸ (Signalling and Telegraph)!)

The "dangly bits" are referred to as "small part steel".  Also, the perceived lack of progress around stations can be partly explained by the fact that the wires will be held up by different types of support.  The most likely type will be a twin track portal arrangement, and that installing this will need fairly major holes to be cut into station canopies and twin track possessions.  Also, there is a gauge clearance exercise to be done too.  The route will be re-gauged to allow W10 and W12 freight wagons to come through, and also to provide adequate clearance for pantographs in accordance with European inter-operability requirements.  This means a measuring and cutting back of the canopies, where the originals are staying, or a rebuild.

Thanks for that - can I ask what is significant about the W10/W12 freight wagons in this respect?

[Visoflex]

Thanks for that - can I ask what is significant about the W10/W12 freight wagons in this respect?

The gauge is dictated by the size of ISO shipping containers.  W10 is a 9'-6" high deep sea container (also known as "High-Cube").  W12 is similar but refrigerated.   This traffic comes through Southampton and needs to go down to Acton or to the WCML^▸ (West Coast Main Line).  These tall containers carried on standard UK^▸ (United Kingdom) freight wagons could potentially hit overhanging canopies.

See here (http://www.greenlogistics.org/SiteResources/cb01cdef-c5ce-4f19-bcf2-a8fd0aac657a_LRN2008%20Woodburn.pdf) for a better explanation

[paul7575]

In real measurements the difference between W10 and W12 is trivial, about 5 cm on the width overall, so an inch each side in old money, so it is almost always an easy win to get W12 rather than W10.   There is no height difference between the gauges.

Another thing about W10 and W12 freight gauges is that they are no higher than 'locomotive gauge' - the work is all about fitting the corners of the boxes through a particular gap.   

One thing that is always true, is that 'electrification' clearance does not automatically bring with it W10/W12 clearance.

I think the comparison drawing that NR^» (Network Rail - home page) use in their RUSs^▸ (Route Utilisation Strategy) etc (attached below) makes the relative sizes clearer - they show all the container gauges as being within the superimposed locomotive for width, and even W10/W12 is the same height.

Paul

[eightf48544]

We had another visit from Crossrail yesterday telling us they will be banging away over the weekend. Don't think it will effect us much as the most of the posts near us are already in place.

[Rhydgaled]

Really makes you wonder just how far behind they really are now.

Can anyone remember when the first section (was it Reading-Didcot, or Didcot-Swindon?) was supposed to be energised ready for IEP^▸ (Intercity Express Program / Project.) testing to begin? Probably was arround now, so we might get an idea of how far the scheme is behind when that first section is switched on.

Another thing about W10 and W12 freight gauges is that they are no higher than 'locomotive gauge' - the work is all about fitting the corners of the boxes through a particular gap.

Square 'pegs' (containers) and round 'holes' (arched bridges and most tunnels) spring to mind.

[IndustryInsider]

Can anyone remember when the first section (was it Reading-Didcot, or Didcot-Swindon?) was supposed to be energised ready for IEP^▸ (Intercity Express Program / Project.) testing to begin?

Reading to Didcot and the end of last month IIRC^▸ (if I recall/remember/read correctly).  Work really appears to have picked up in pace with many areas now looking ready for the wiring train.  That said there are several locations, mostly around the stations, where there are no sign of gantries as yet - as Visoflex and Berkshire Bugsy were discussing earlier.

If the recent rate of progress is maintained then I'd bet on delivery less than six months late for that section.

[Tim]

Square 'pegs' (containers) and round 'holes' (arched bridges and most tunnels) spring to mind.

Indeed,  One of the options for gauge enhancement is to replace an arch bridge with a beam bridge without needing to raise the overall bridge height at all.

Paul7755's link was informative (thanks).  It makes it clear why all this fright gauge enhancement work has little affect on taking us any closer to double decker passenger trains as in Europe, which need extra height in the centre rather than squared-up corners.

[Tim]

Work really appears to have picked up in pace with many areas now looking ready for the wiring train.  .

Does that mean that they have now started to get the hang of the new German work train which were introduced with such fanfare (didn't the Queen name it)?  If so then that is indeed good news for the future as the current issues can be viewed in large part as teething problems rather than anything more permanent . 

[IndustryInsider]

Well, it's out pretty much every night, split into various sections with hundreds of staff beetling about nearby.  I still have my doubts as to it ever getting close to the efficiencies expected of it though!

[TonyK]

Leaving BRI^» (Bristol Temple Meads - next trains) for SWI^» (Swindon - next trains) this morning, I spied a lorry load of piles (about 6) unloading at the siding behind Avonmeads. I don't know where they are made, but it's kind of sad to see them arrive by road.