Bletchley flyover

[@jeffreyloftus3617]

Those pre-cast box beams are a brilliant idea so much more easier than shutters and the finished product is far better than any cladding / shutter finish

[@chrisfryer3118]

that's a lot of concrete and steel, looks bombproof.

[@dolanbaker]

That replacement flyover is considerably more substantial than the one built in the 1960s, do they hope it will last longer than 60 years!

[@nickhubbard3671]

Very impressive.

[@HSMiyamoto]

Watching the crane place all those concrete blocks makes it look like you are playing the world's largest game of Minecraft.

[@railfreightdrivergallagherGBRf]

Well, this new one sure looks like it's built to last more than 60 years! It's very substantial compared to the 1960s one it's replacing!

[@GeneralThargor]

I noticed that too, that is one bloody strong structure they've built there.

[@jimthorne304]

I do wonder if this project will actually be completed; the govt. has considerable form relating to abandoned rail projects and the connection through to Cambridge is still not agreed.

[@michaelstevens3479]

Is it in their contract that the machines will not work without the music?

[@stbu9709]

Faster the beat, faster they work! 👷‍♂️

[@KimTebrok]

Hope the public use the railway.

[@noneseneguy]

They will if and when the Central Eastern leg from Bedford to Cambridge gets the go ahead by the Government.

[@jasonowen5450]

Its hard to imagine, but in 10years those new looking concrete blocks will be covered in Graffiti and Urine.

[@tracynation2820]

Great video. 💙 T.E.N.

[@joginns778]

Where is the new station going and is old fennystation comeing out of use on the Bedford line

[@sjcsystems]

There is going to be a high level station on the new tracks between the existing station and the concrete works

[@johnson_street_IEMD]

great video ... is this bridge for a railway crossing as such ... ?

[@ds1868]

It will be the elevated section of East West Rail for Bletchley. The platforms will also be elevated and integrated with the flyover. This is a rebuilt railway line between Oxford and Cambridge costing nearly £6 billion. It will be a 100 mph railway with full W10 loading gauge for freight.

[@sjcsystems]

@@ds1868 but not electrified - the original proposal was for electrification but removed due to cost cutting

[@dwainemckoy9625]

@@sjcsystems not electrified?! Surely if they run diesel trains on this route wouldn’t it cause more pollution?

[@sjcsystems]

@@dwainemckoy9625 They may be hybrid trains, but no the wires were abandoned some years ago. Utterly stupid. I've been involved in East West Rail as a supporter from almost the beginning.

[@dwainemckoy9625]

@@sjcsystems Most probably a battery/diesel hybrid train. I agree with you It’s nuts they abandoned installing overhead wires. Seems like a lot of planned overhead wire installations on the UK’s railways have been either shelved or completely abandoned.

[@bebtozoltan55]

Bletchley Park

[@johnhealy8513]

Good video apart from the irritating music.

[@frasermitchell9183]

This project is certainly under the Greenie Loonies radar

[@professorjamesmoriarty5191]

They cant moan about it, the railway was already there

[@haydonsheard2168]

All they can do is try to build sustainably on this site which is most likely brownfield site anyway

[@sjcsystems]

@@haydonsheard2168 except for the section between Bedford and Cambridge

[@haydonsheard2168]

@@sjcsystems is some of the alignment being moved

[@bfapple]

@@haydonsheard2168 The South Cambridgeshire villagers are incensed that anyone would dare to undertake any kind of building work near them. However the worst hypocrisy is the St Neots “mayor”, who says the railway (and St Neots South station) shouldn’t be so close to the thousands of houses they are building on greenfield land!

[@shahedmc9656]

Great video and music. Who's the composer?

[@almostanengineer]

Song information is in the description.

[@shahedmc9656]

@@almostanengineer thanks!

[@geoffreystevens663]

Nice video shame about the 'music'

[@shahedmc9656]

What? the music's the best part!

[@sandycheeks7865]

Any 1st world country building a new diesel-only railway line should hang it's head in shame.

[@cmclewee9518]

I am fully supportive of this new railway, but I would love to know why every structure put in place by network rail seems to be constructed from concrete lego components. Whether its this project, Dawlish sea wall, Even HS2 seems to be being built out of giant lego bits. Why was this not poured locally into concrete forms and save all the transport costs of moving it all around the country. The aggregates could be bought in by rail and nothing needs to be on the road. Plus precast bits will never be as strong as poured concrete too many joins which weaken the structure and allow in the weather to corrode the reinforcing. I would be surprised if this lasts more than 30 years.

[@freegs]

Hi Colin, offsite manufacturing such as pre cast concrete components allows for significant increases to safety/quality/emissions and performance efficiencies.

[@cmclewee9518]

@@freegs Hi Tom, I am not a civil engineer but am a marine engineer of 45 years experience, I just cannot see how offsite manufacturing can be stronger or more efficient when you have so many pieces. All the joins between the various blocks will surely weaken any structure. Surely pouring a support as one composite piece rather that standing a number of Lego bricks on top of each other.is stronger and how can that possibly be cheaper. Plus you have all the transportation cost of bringing them to site. Those beams that have been used to make the box a bletchley would have surely been stronger if it was poured on site into forms thereby negating all the gaps between the beams. How will that ever be made watertight as they were just lifted and put next to each other. Plus all the rebar was exposed at the ends of each beam there by allowing rusting. I was always led to believe that rebar had to be buried a certain depth into a structure where these beams have exposed rebar. As an engineer I just see this as dumbing down of skilled work to labourers that would have been done by skilled construction teams.

[@freegs]

@@cmclewee9518 Hi Colin, for background, I'm a construction materials engineer who's worked on some of the most complex reinforced concrete structures in the UK (including nuclear). Precast factories yield better quality and strength as they provide optimal manufacturing and curing conditions and relative to site works, massively more control. On site you're at the mercy of ready mix suppliers, the Great British weather and curing is often undervalued and imperfect (big determinant of concrete quality and durability). You mentioned the aggs could be transported into site via rail, where are they batched and under what controlled conditions? You're correct that a fundamental of reinforced concrete quality is nominal cover to reinforcement (mm) and this will be stipulated in the spec. All precast items would have to meet the same values as in-situ poured concrete except it's much better controlled in factory conditions. With regards to the gaps, this isn't an issue as they are primarily static joints which are only stressed in compression. The argument about pathway for water ingress is not true because of the equivalent cover as I've mentioned and the fact that durability (porosity and chloride migration) will be improved in factory precast items. Furthermore, excellent joint sealing products exist which are infinitely more protective than concrete and these may be employed if deeemed necessary by the designer. Design life for most heavy civils works is 100 years and more computational modelling, trial work and materials testing is done than ever before. Modern methods of manufacturing using modular items and BIM/computer modelling yields greater quality, cost, speed, safety and wastage otherwise contractors wouldn't do it. It's not all empty rhetoric in the industry regarding efficiency, it's the reality of modern construction 👍

[@freegs]

Wanted to add that if it was the Dawlish sea wall or any structure in the marine environment (especially intertidal zone which experiences drying) your multiple joint argument would be much more important.

[@cmclewee9518]

@@freegs Tom, thank you for your very informative reply, it just shows how different industries have evolved over recent years. I was mainly referring to the Dawlish sea wall project but equally to east west rail, where the majority of work appears to be precast. Your second reply was really relevant as the jointing between the precast panels has already failed after just one winter season and the panels are already covered in rust marks which leads me to believe that that structure will not last its supposed 120 year life. I also don't understand why the panels and wave units were made in Ireland for a job in Devon. That surely cannot be good use of taxpayers money. As a marine engineer we spent years trying to combat corrosion but it is not easy, but little attention seems to have been paid to this at Dawlish and after less than 12 months the corrosion either inside or behind those panels is obviously winning. There was logic why Brunel built the original structure in stone and cement, namely no steel was involved. Unfortunately Network Rail have chosen a material totally unsuitable for the task. No matter how well you protect the steel, steel and Saltwater are not good companions.

[@sjcsystems]

How ridiculous that lorries are delivering those sections when adjacent to a railway...only in the UK...

[@normaneckley9332]

Perhaps they were delivered by rail to a nearby siding that didn’t have the complication of overhead lines ?

[@lolzlolz69]

You want to close down the WCML every time there is a delivery?

[@sjcsystems]

@lolz lolz...utter stupidity. There is plenty of space on either side for a temporary siding or loop. No wires over. Just like the maintenance siding at Blisworth Station... how many lorry journeys would have been saved...

[@lolzlolz69]

@@sjcsystems You clearly have no clue on what it takes or how much to add a rail siding, connection to the mainline and associated unloading facilities. Go back to your Hornby.

[@garyparker2541]

I think that the length of the sections means that they cannot take curves, so theoretically, they would have to be made right by the track - and then loaded onto purpose built bogies, and then only travel on straight lines. This would also be costly, impractical and probably just not possible?

[@chairmakerPete]

Very impressive, but could it be more ugly?

[@matthewtierney2963]

Bletchley or the flyover?

[@peebee143]

A bit different to the earlier flyover.