Cost of Viaducts

[HSTEd]

Well I have a bit of an odd question.

Are there any up to date figures for building long viaducts that are level and not particularly tall with the primary purpose of carrying the railway tracks over a city? perhaps over an existing railway or road alignment rather than to reduce gradients.

 

[ntg]

As in...the cost of building elevated rail networks? Maybe look at the DLR costs?

 

[Clip]

As in...the cost of building elevated rail networks? Maybe look at the DLR costs?

Majority of DLR is all pre fabricated and itsnt actually that high either and in the main either follows parts of disused rail line or has been built in areas where there was nothing there before - think docklands itself and then out past UEL and onto Gallions reach.

This sort of early building would be far cheaper then trying to build again in a denseley populated area. Though Im not sure what the proposed costs are for the extension to Dagenham should it ever get off the ground.

 

[Tin Rocket]

How much do you think it would cost in todays money to build harringworth viaduct?

 

[Ploughman]

How much did the Medway viaduct cost?
That might put you in the ballpark.

 

[Bald Rick]

My guess for double track is about £5m base + £1m per 10 metres, assuming you buy more than 100 metres. This is pure bridge costs, i.e. excluding land or rail infrastructure costs or any approach earthworks etc.

Real examples -

The total cost of all the major structures on CTRL Phase 1 was £372m at 2003 prices. This included the Medway viaduct, Ashford viaduct, and all the standard bridges, but not any tunnels. This was approx 20% of the total cost of CTRL Phase 1. So if you're costing a new railway along similar terrain as rural Kent, then a figure of £5.1m for bridges per km of new railway (+ inflation) will see you in the right ballpark.

Cost of replacing the Catthorpe viaduct where the southbound M6 crosses the M1, basically 100metres of 3 lane motorway bridge, is £21m.

TfL might give you the numbers for the Shoreditch viaduct immediately north of Shoreditch High St station on the ELL where it turns to join the old Hoxton viaduct. I watched that being built every day for 2 years - it took a lot of people, a lot of rebar and an awful lot of concrete.

 

[dalmahoyhill]

Tin rocket

well its easier to construct a viaduct of harringworths length nowadays. all those bricks for a arch viaduct, that's a lot of hands on work!
nowadays it would be a concrete balanced cantilever structure with spans between piers of 50-100m long. I was searching for costs for comparative motorway viaducts and couldn't find anything. gut feeling is £100mill approx.

Building in a built up area is significantly more expensive due to access difficulties. constructing the piers when there is likely to be services and variable ground conditions. Cost of acquiring land and renting additional land for construction.

I will see what other costs i can dig out.

 

[Tin Rocket]

Tin rocket

well its easier to construct a viaduct of harringworths length nowadays. all those bricks for a arch viaduct, that's a lot of hands on work!
nowadays it would be a concrete balanced cantilever structure with spans between piers of 50-100m long. I was searching for costs for comparative motorway viaducts and couldn't find anything. gut feeling is £100mill approx.

Building in a built up area is significantly more expensive due to access difficulties. constructing the piers when there is likely to be services and variable ground conditions. Cost of acquiring land and renting additional land for construction.

I will see what other costs i can dig out.

Dalmahoy
you have to quote for a like for like brick viaduct,using prefab concrete is cheating

 

[HSTEd]

I was actually pondering building a high speed railway line on a viaduct above an existing railway line to get into the centre of a city without having to interfere with the existing railway's operations or undertaking enormous demolitions that would be rather unpopular.

Dalmahoy
you have to quote for a like for like brick viaduct,using prefab concrete is cheating

Get the stick-a-brick?

 

[DaveNewcastle]

I was actually pondering building a high speed railway line on a viaduct above an existing railway line to get into the centre of a city without having to interfere with the existing railway's operations or undertaking enormous demolitions that would be rather unpopular.

Two recent spans come to mind then:-
The link between the M8 and M74 motorways in Glasgow. Although it was a road spanning over the WCML (and other roads), it was done by slowly sliding the pre-assembled road section over the railway during the winter of 2009-10.

The new twin-track railway bridge over Borough Market in London, again positioned by slowly sliding the pre-formed railway bridge over the market (and with only centimeters clearance from occupied buildings on each side).

If you think they'd help, you could try searching for prices for those recent contracts?

 

[Bald Rick]

I was actually pondering building a high speed railway line on a viaduct above an existing railway line to get into the centre of a city without having to interfere with the existing railway's operations or undertaking enormous demolitions that would be rather unpopular.

If viaducts above existing lines were cheaper and easier, there would be a nice new viaduct from Stratford to St Pancras via Dalston, rather than the tunnel that runs directly beneath.

Bored Tunnels - North Downs tunnel was roughly £100m for 3.2km in perfect conditions (chalk) in 2003 prices.

Crossrail - 18 km twin bore for £1.25bn (excluding TBMs and portals) in 2010 prices.

 

[HSTEd]

If viaducts above existing lines were cheaper and easier, there would be a nice new viaduct from Stratford to St Pancras via Dalston, rather than the tunnel that runs directly beneath.

Bored Tunnels - North Downs tunnel was roughly £100m for 3.2km in perfect conditions (chalk) in 2003 prices.

Crossrail - 18 km twin bore for £1.25bn (excluding TBMs and portals) in 2010 prices.

I think part of the problem with new viaducts (anywhere) is that they are rather hard to get past the planning system as everyone within half a mile of the viaduct will complain either about the view or the loss of privacy or whatever.

Ofcourse the cheaper solution compared to a bored tunnel if massive disruption to the original line was acceptable would probably be to dig a hole and put the track inside it.

 

[Bald Rick]

For long stretches, bored tunnels are generally still cheaper than cut and cover. Once a TBM has been paid for, it's just a case of muck out, concrete rings in. Very labour efficient, no temporary works, no trouble from the neighbours. Unless your house falls in a hole.

 

[dggar]

.......

This sort of early building would be far cheaper then trying to build again in a denseley populated area. Though Im not sure what the proposed costs are for the extension to Dagenham should it ever get off the ground.

Would it be cheaper to leave it on the ground

 

[HSTEd]

Do we have a price for a project longer than the Crossrail one so that we can work out what hte price per kilometre is once the cost of the TBM has been accounted for?

 

[Trainbuff]

Any ideas of cost to replace this structure if ever contemplated? Maybe 200m long.

 

[Bald Rick]

Do we have a price for a project longer than the Crossrail one so that we can work out what hte price per kilometre is once the cost of the TBM has been accounted for?

You'll find everything you want by digging around (sorry) on the Crossrail website. You'll also need to add in costs of portals, spoil disposal, and a concrete ring factory.