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HS2 under review


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11 hours ago, rockershovel said:

re Mike Storey, above, an "enhanced street level walking route" would surely include an underpass or overbridge for the chaotic road crossing West of Kings X! 

 

You would hope so, but I have been unable to find out much more about it so far. Just pretty pictures of lots of trees and a very wide pavement.....

 

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1 hour ago, lmsforever said:

Big concentrations of construction equipment at Great Missenden and route has fenced off northwards wonder when the tunnel machines will arrive?

I suspect a good while after the start of construction.  From watching programmes about other tunnelling projects they need to build quite substantial structures to act as what I think are called, launch portals first.   They also need to have enough concrete standing to erect all the tail of the machines which can be at least 100 yards long.  I would hazard a guess at about a year till the TBM's start to arrive but will be happy to be corrected.

 

Jamie

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8 hours ago, jamie92208 said:

I suspect a good while after the start of construction.  From watching programmes about other tunnelling projects they need to build quite substantial structures to act as what I think are called, launch portals first.   They also need to have enough concrete standing to erect all the tail of the machines which can be at least 100 yards long.  I would hazard a guess at about a year till the TBM's start to arrive but will be happy to be corrected.

 

Jamie

 

That would be a reasonable estimate, and you also need to add in the very probable need for a concrete batching plant for such a major construction. Whilst I don't know if they intend to use pre-cast liners, you would still need a significant amount on top of that. It is unlikely you would bring it in "wet" by road in those quantities.

 

There will also need to be a very large area devoted to spoil. If they are to re-use a large amount of that, to create embankments elsewhere, it will need separating and grading, before despatch. No point sending out a load of mixed spoil for which engineers could not determine compaction and thus settlement rate, and rapid settlement, probably mechanically assisted, will be needed to construct within timescale. In other situations, you could dump whatever you liked, and leave it to settle for 10 years or so, and test compression by weights (usually large, caged blocks of bricks). For the only railway embankment I ever project managed (a pretty short curve to widen an existing one), for the 2012 Games, it had to be done PDQ, and we had to buy in a huge quantity of three differently aggregated layers (important for both settlement and then drainage) and mechanically compress it layer by layer. For the main Games, working to an immovable deadline, whilst we had a huge soil re-use, cleaning and separation operation, settlement would have still been inadequate and most major structures had to be piled down, almost to the Earth's molten core...... I watched a significant part of the construction of the LGV Atlantique line from Poitiers to Bordeaux, which passes not far from here, which includes huge lengths of embankment and cuttings (what else do you do on wet Wednesday afternoons?). They built up the embankments (mostly from the cuttings) over a period of about two years, in at least two layers, but could have been more - I did not see the earliest stages soon enough - and rolled and rolled each layer using absolutely enormous machines, before the next one, then let it settle for about a further two years whilst they built the many over and under bridges.  Expect HS2 to do something similar. 

 

But this is HS2. Given the paralysis currently reported over possible design changes to max line speeds (to prospectively reduce construction costs), especially in tunnels, one wonders if there is yet a "final" design? The design speed will determine the approach cutting and portal minima and the dimensions of the tunnel itself, at least at the first few hundred metres.

 

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Having had a certain amount of experience of such construction, I’d offer a few comments

 

https://www.chilternsaonb.org/uploads/files/high_speed_2/Feasibility Study of Tunnelling Options for High Speed Rail in the Chilterns FINAL Rev AC.pdf

 

1) segments aren’t usually made on site. They require quite a major facility which will probably be purpose-built by the specialist supplier, or an existing facility re-purposed.

 

2) TBMs usually have a “short” launch configuration, and are assembled to full size as the tunnelling progresses because of space reasons, and to better manage the handling of power connections, outbound arisings and inbound materials

 

3) depending on the type of TBM, there will be a major facility for handling outbound arisings, as close to the portal as possible UNLESS some sort of intermediate facility is constructed at a temporary driving shaft. It’s usually more cost effective to accept longer runs to the portal, given that you have a railway sized profile to work with. TML ran their construction rail system as a stand-alone entity and I dare say this would be done the same way, there’s a lot of experience available

 

4) there will be a detailed plan for the disposal of arisings, it’s a major cost element. If the main arisings are Lewes Chalk then they are not the best construction material in the world, but there is a lot of experience of using them as fill, and that would be the most likely plan.

 

if geology is variable, or unsuitable for fill that’s a different subject entirely, but that’s not a preferred design parameter

 

Ideally such projects are designed to be “fill-neutral” with quantities of cut and fill being balanced and haul distances minimised, but that’s a very large subject - at TML, there was an available tip site and a use for the infilled area; at Jubilee Line Extension, a major water-borne operation took the clay arisings (and virgin London Blue Clay, in bulk, is a valuable resource) to Greenwich to provide the capping to the contaminated site where the Dome/O2/whatever it’s currently called stands; at the London Water Ring Main project in the 80s, the London Clay was hailed by Road and much of it ended up in embankments on the M25, which is fill-negative overall. 

 

 

Edited by rockershovel
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In the planning / approval stages, HS2 had a large full surplus. They were touting round to all takers. EA were being encouraged to find homes for fill as flood defences across England. Local Authorities were also working with HS2 to use spare fill in new bypasses and the like and am involved in one such scheme myself.

 

ive heard from HS2 contacts recently that the detailed design is moving towards a fill-neutral position. Whilst that’s good for HS2 and it’s contractors, it’s not so good for those who’s own projects & funding assumed getting the surplus.

 

 

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12 hours ago, Mike Storey said:

 

There will also need to be a very large area devoted to spoil. If they are to re-use a large amount of that, to create embankments elsewhere, it will need separating and grading, before despatch. No point sending out a load of mixed spoil for which engineers could not determine compaction and thus settlement rate, and rapid settlement, probably mechanically assisted, will be needed to construct within timescale. In other situations, you could dump whatever you liked, and leave it to settle for 10 years or so, and test compression by weights (usually large, caged blocks of bricks). For the only railway embankment I ever project managed (a pretty short curve to widen an existing one), for the 2012 Games, it had to be done PDQ, and we had to buy in a huge quantity of three differently aggregated layers (important for both settlement and then drainage) and mechanically compress it layer by layer. For the main Games, working to an immovable deadline, whilst we had a huge soil re-use, cleaning and separation operation, settlement would have still been inadequate and most major structures had to be piled down, almost to the Earth's molten core...... I watched a significant part of the construction of the LGV Atlantique line from Poitiers to Bordeaux, which passes not far from here, which includes huge lengths of embankment and cuttings (what else do you do on wet Wednesday afternoons?). They built up the embankments (mostly from the cuttings) over a period of about two years, in at least two layers, but could have been more - I did not see the earliest stages soon enough - and rolled and rolled each layer using absolutely enormous machines, before the next one, then let it settle for about a further two years whilst they built the many over and under bridges.  Expect HS2 to do something similar. 

.

 

Earthworks are the foundation to all infrastructure and my daily working life.

 

compaction of fill material is essential and even the biggest rollers can only compact a few hundred millimetres of fill in one go and even then will need many passes to do so. There are published charts for this and a lot of insitu testing to confirm.  These techniques take out upwards of 95% of the settlement

 

its quite a science / art form and transfixing watching a well organised team.

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Rather unsurprisingly Crossrail had a large surplus of spoil.  Where extracted at the eastern end this was loaded directly onto barges, and at the western end it went by train over half way round London to be loaded onto barges on the lower Thames.  It was used to create a new nature reserve in Essex. 

 

http://www.crossrail.co.uk/news/articles/wallasea-isl-jetty-completed-as-crossrail-helps-rspb-shape-europes-largest-new-nature-reserve

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Simon Jenkins flies a kite about HS2 being cancelled by Liz Truss in t'Guardian:

https://www.theguardian.com/commentisfree/2019/apr/16/scrap-hs2-north-hs3-rail-commuter-journeys

 

The kite is stitched together out of Trumplike simplifications and falsehoods, and he has an agenda as Chair of the National Trust. The question is whether the kite is attached to any reality?

 

 

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2 hours ago, Dava said:

Simon Jenkins flies a kite about HS2 being cancelled by Liz Truss in t'Guardian:

https://www.theguardian.com/commentisfree/2019/apr/16/scrap-hs2-north-hs3-rail-commuter-journeys

 

The kite is stitched together out of Trumplike simplifications and falsehoods, and he has an agenda as Chair of the National Trust. The question is whether the kite is attached to any reality?

 

 

 

Thanks for this. Jenkins, as usual, has his facts skewed. Rail carries 11% of all passengers by journey x distance (nearly double that of 20 years or so ago). He proffers the myth that upgrading existing lines is a far superior and cheaper option. The man is being his usual charlatan self - by his measure (using any journey to count towards the total), 26% of all journeys are made on foot, so any fule could conclude that much more should be spent on improving pavements between London and Scotland.

 

When one reads through the comments, the level of ignorance (whatever your opinion about HS2) is alarming. I fear for the economic, social and environmental future of the UK. Thrashing about with bloke-in-the-pub's "common sense" about how to solve the railways, will lead nowhere, and will just give certain politicians a grand excuse not to spend any money at all on public services.

 

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Jenkins' source turns out to be Katie Balls' puff-piece in The Spectator [FFS!] about Liz Truss's Tory leadership ambitions. Tendentious in the extreme. Journo's trying to make up the news. Here it is:

 

 " Might she be tempted to save money by abolishing HS2? Truss has previously hinted the troubled £56 billion high-speed rail project could face the axe as part of a review of ‘all major investment projects across government’. Today she confirms the project will feature in the review. Asked if she would scrap HS2, Truss replies: ‘That’s a matter for the zero-based capital review that I’ll be looking at very intently’. Truss intends to weed out projects that are failing or over-budget. ‘What really drives local economies is transport around counties. Transport into cities. That’s what makes a difference to why a business decides to locate somewhere. We have to be rigorous about what infrastructure is going to maximise opportunities for people.’ This doesn’t sound like a manifesto for keeping HS2.".

 

Journos and politicos in pursuit of their careers above all else. No further comment.

 

 

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9 hours ago, Mark Saunders said:

The whole of British Politics has been based on short sight since the late 1970's and the long term plan forgotten!

 

Using the logic of those opposed to spending on HS2 why was the Motorway network built when there was an existing network of Trunk Roads!

 

 

 

Completely spot on!!

 

Current road policy is similar to the anti-HS2 junkies' wishes - widening of existing A roads, "smart" upgrades of motorways, widening the M25 car park etc. Every single one of these jobs is very lengthy, highly disruptive, and pretty much redundant when completed (being full, or just moving the traffic jams further on). I don't advocate new roads (bar the odd by-pass or link road to public transport interchanges) whatsoever, in the UK - that horse bolted, as a solution, many years ago, thank goodness. Mass transit expansion is the only sensible future in a very crowded island. Whether that should just be parochial or national is the current debate. (It should be both for goodness sake.) Stephenson wasn't commissioned to build a railway from Birmingham to London because it would harm the fortunes of Birmingham......

 

But why do so many people think that upgrading what we have now, having done that for many decades and everything is still bursting, is a perfectly acceptable solution for rail? Bonkers.

 

And I include the Judean Peoples' Front to Re-open-the-Great-Central in that, despite that being probably the most disruptive and ineffective thing of all disruptive and ineffective things. And they will be set against the People's Front of Judea to Re-open the etc etc, (who have a slightly different idea) to enable the Government to defer any decisions for ages and ages. Just look at how they are turning HS3 into a bit of haphazard electrification and a few longer platforms, whilst the Quangos and DfT argue amongst themselves over the long term solution. Classic politics from The Treasury.

 

Whatever you think of the selected HS2 solution, it is all too easy to lose any chance of a step change in UK rail's capacity, just by playing the populist, largely ignorant (of railway matters in this case) and tub-thumping game. There will not be a generous alternative. We have seen it all before.

 

 

 

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3 hours ago, Mike Storey said:

 

Current road policy is similar to the anti-HS2 junkies' wishes - widening of existing A roads, "smart" upgrades of motorways, widening the M25 car park etc. Every single one of these jobs is very lengthy, highly disruptive, and pretty much redundant when completed (being full, or just moving the traffic jams further on). I don't advocate new roads...

 

 

 

Why not?

 

You think HS2 is now justified because the current rail network is so successful that extra capacity is needed.

 

The road network has been massively more successful. Logically we should build more roads.

 

 

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"And I include the Judean Peoples' Front to Re-open-the-Great-Central in that, despite that being probably the most disruptive and ineffective thing of all disruptive and ineffective things."

 

Just to be clear, you are opposing [ridiculing] the project to reunify the GCR from Ruddington to Birstall as a heritage railway?

 

No-one is seriously proposing to reopen the GCR as a trunk route. Not since the 'Grand Central' fantasy of 20+ years ago.

 

Dava   

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There is still a lot of road building and widening going on but not at motorway level.

 

some trunk roads are being upgraded to motorway standards by HighwaysEngland , eg A14, A47, A66 and A303. HE have a huge budget for such works alongside smart motorway upgrades.

 

New motorways suffer the same problems as HS2, highly vocal

opposition groups, unco-operative landowners, slow & expensive planning approvals etc. Far easier to spend the same money fixing  issues at a more local ‘county’ level

 

many others are being rebuilt or new bypass roads created by local authorities. Many £bns are available for these projects over the next 4 years, lobbying and sponsoring of the bigger schemes now resting with the regional transport quangos alongside the owning Highway authority. Part funding comes from housebuilding land opened up by the new road.

 

For examples, there is over £1bn of such works planned acrosss Yorkshire, £500m in Bucks, £500m in Oxon

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7 hours ago, Dava said:

"And I include the Judean Peoples' Front to Re-open-the-Great-Central in that, despite that being probably the most disruptive and ineffective thing of all disruptive and ineffective things."

 

Just to be clear, you are opposing [ridiculing] the project to reunify the GCR from Ruddington to Birstall as a heritage railway?

 

No-one is seriously proposing to reopen the GCR as a trunk route. Not since the 'Grand Central' fantasy of 20+ years ago.

 

Dava   

 

No, of course I am not referring to the heritage project.

 

It has been the regular assertion that re-opening and upgrading the entire GC route would be easier and cheaper than the existing HS2 plan, which was proven to be untrue a long time ago (the 2010/11 evaluation reports primarily). That is not to say some aspects of it for a slightly revised route may have had merit.

 

The main point is that the continuous bickering over detail, but by people who do want to see a new route opened, will only aid those who want to see nothing built at all.

 

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5 hours ago, black and decker boy said:

There is still a lot of road building and widening going on but not at motorway level.

 

some trunk roads are being upgraded to motorway standards by HighwaysEngland , eg A14, A47, A66 and A303. HE have a huge budget for such works alongside smart motorway upgrades.

 

New motorways suffer the same problems as HS2, highly vocal

opposition groups, unco-operative landowners, slow & expensive planning approvals etc. Far easier to spend the same money fixing  issues at a more local ‘county’ level

 

many others are being rebuilt or new bypass roads created by local authorities. Many £bns are available for these projects over the next 4 years, lobbying and sponsoring of the bigger schemes now resting with the regional transport quangos alongside the owning Highway authority. Part funding comes from housebuilding land opened up by the new road.

 

For examples, there is over £1bn of such works planned acrosss Yorkshire, £500m in Bucks, £500m in Oxon

 

And many of those are running years, even decades late - the A47 being a classic.

 

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8 hours ago, locoholic said:

Why not?

 

You think HS2 is now justified because the current rail network is so successful that extra capacity is needed.

 

The road network has been massively more successful. Logically we should build more roads.

 

 

 

That was the thinking of the 1960's to 1980's, and led to massive new road networks. It simply proved that more roads means more traffic, and solved little. Capacity drove demand.

 

Rail demand has risen exponentially with only marginal increases in capacity in the last 30 years, so your comparison is regrettably, completely flawed.

 

 

 

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All this British style faffing around with HS2 makes me weep - GET IT BUILT !!

 

Watch this what China are up to - Road, Rail, Sea, Air.

 

Look at the new yard for electrically hauled coal trains at 50.03. (THEY are not bothered about climate change).

 

 

Just makes the UK look so insignificant these days.

 

Meanwhile, back at home

 

Crossrail could be delayed until 2021, according to a senior source associated with the project to build a new railway underneath central London.

 

https://www.bbc.co.uk/news/business-47967766

 

Brit15

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9 hours ago, locoholic said:

Why not?

 

You think HS2 is now justified because the current rail network is so successful that extra capacity is needed.

 

The road network has been massively more successful. Logically we should build more roads.

 

 

 

You are a Bus owner in Titfield, and I'm claiming my 2/6d.

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1 hour ago, Mike Storey said:

 

That was the thinking of the 1960's to 1980's, and led to massive new road networks. It simply proved that more roads means more traffic, and solved little. Capacity drove demand.

 

Rail demand has risen exponentially with only marginal increases in capacity in the last 30 years, so your comparison is regrettably, completely flawed.

 

 

 

Road traffic has increased in the same way. The "thinking" that providing extra capacity stimulates extra demand also applies to railways, or didn't you realise that? It is your logic that is completedly flawed, due, I suspect, to an understandable sentimental bias in favour of anything that runs on rails.

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56 minutes ago, 298 said:

 

You are a Bus owner in Titfield, and I'm claiming my 2/6d.

No, I am just a car owner who lives miles from the nearest station, but who was nevertheless planning a rail trip to Scotland. A small change in my plans to travel on a Saturday rather than a Friday means that the journey time is nearly double, due to replacement bus services on the WCML, instead of diversions via the S&C. I shall therefore be driving. The modern railway is expensive, unreliable and inconvenient. Building more of it in the current climate is sadly of very questionable benefit to ordinary taxpayers.

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But the only reason it is unreliable is the lack of investment, in favour of road, over the past 40 years. Now that attempts are being made to rectify this all some folk seem able to do is moan. Rail is an effective and relatively green way to move large volumes of people over a given route. Again the inconvenience of starting point and destination not being exactly where we want to go can, again, be placed, in part, to the lack of investment.

 

Short term disruption is inevitable as there is no longer, due to demand, sufficient time when services are not running to allow essential maintenance and renewals to take place. The only answer is increased capacity, the debate should be around how we achieve that, should it be by upgrading existing lines at very great expense or building new lines (albeit in limited numbers) which are actually cheaper to create than upgrading Victorian infrastructure. Replacement bus services may be the only choice on some routes as the work may be such that diversionary routes are not accessible even though, on the face of matters, they should be. The centralisation of signalling may well be partly to blame but there will, no doubt, be other factors as well.

 

Many would also argue that there is an infrastructure of closed lines that would be easy to bring back into use. I suspect that would not be the case as what remains has not been maintained, has been encroached upon and may well prove to be more expensive to re-instate than building on greenfield land. Indeed many of these lines may also not serve the areas that really would benefit from a rail service in the modern world.

 

And I am a car owner who often finds that it is cheaper, even on my own, to travel by car rather than use the train. I was looking at a journey a couple of days ago and it will cost roughly three times as much to go by train as by car and take longer due to my start and finish points. I agree that the pricing is unrealistic if we wish to use rail as a 'green' alternative to the motor car. However do we all contribute a small amount to a service used by a minority of the population or do we move the whole of the burden to the user. The latter has been the rationale for many years now, is it time for a rethink despite the howls of anguish it will undoubtedly create?

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