Hammersmith flyover closed

[LittleWheelsandBig]

There is no 'may' about it. I spent years working with the Highways Agency and there are hundreds of bridges of all sizes with varying degrees of deterioration.

The high-strength steel used for prestressing is inherently prone to corrosion, workmanship on British highway structures in the 50/60/70's tended to progressively decline (due to ministers liking to boast about how many miles had been built during their time in office) and because many structures' poor design choices are only becoming apparent decades down the line. Stressing bars occasionally blast out of bridges, suspension cables gradually lose individual wires (Forth Road Bridge for one) and tendons invisibly corrode. Meanwhile, the lorries get bigger.

Replacing, strengthening and maintaining these structures (with the huge forces involved) is tricky, particularly since money for infrastructure is being cut while the problem is growing.

[matthew]

Everyone builds infrastructure on a cost benifit analysis over 50 - 100 year design periods, they include maintanence in that analysis and the project is approved and the capital found to construct it. However at teh same time the maintenance capital is not written into the next 100 years of budgets. Then 25 5 years later they look for budget savings (efficiencies) and maintenance budgets get cut, not capital as senior managers and politicians like to open new structures and say we spent £xbn and there is nothing to show for it doesn't play well.

So you are constently adding to the maintenance liabilities with new 'assets' and cutting the funding to meet those liabilities.

[marcusjb]

Opened to cars only, one lane in each direction as of this morning.

Hopefully will make things less awful around here, but the one lane only will be in place for around 4 months.

Riding in and out of town has been a bit hairy at times, so hopefully things will be a little better from now. Though, of course, I expect all the motons who've sensibly chosen to use the tube this week to leap straight into their cars this morning at the news of the opening, so chaos may continue.

[Psychler]

From TFL

Hammersmith flyover to reopen for cars and light traffic as vital repair works continue

·         Flyover to reopen one lane in either direction for cars, vans and other light traffic

·         TfL continues to work round the clock to reopen bridge to all traffic over the next four months

·         Drivers advised to continue to plan routes carefully and avoid area if possible

Transport for London (TfL) will be able to re-open one lane in each direction of the Hammersmith Flyover to cars, vans and other light vehicles, before tomorrow morning’s rush hour, following confirmation from structural engineers and leading independent experts that the flyover is now safe to take light traffic.

One lane of light traffic will now be permitted in each direction, whilst work continues to strengthen key sections of the flyover. Traffic restrictions will be enforced by a 2.0m (6”6’) width restriction at either end of the flyover to prevent large vehicles such as HGVs and coaches from crossing.

The structural repair works, which TfL now expects to take around four months to complete, will focus on strengthening six of the 16 spans of the structure to ensure that they can carry full traffic loading by the Olympics.

The advice remains for motorists as this work takes place that as the flyover is not fully open they should consider avoiding the area if possible. Transport for London will have signage and traffic management measures in place to help reinforce that.

Once these repair works, which will see new cables installed within the structure to strengthen the flyover, are completed, TfL will be able to reopen the flyover to all traffic, well ahead of the London 2012 Games.

Following the London 2012 Games, TfL will return to the structure to strengthen the remaining ten spans of the flyover, as well as carry out additional work to re-waterproof the entire road deck to complete the permanent repair.  This work is expected to take place in a way that will allow as much traffic as possible to use the flyover during the works.

Boris Johnson, Mayor of London, said: “I made it very clear the Hammersmith Flyover should not be closed for one minute longer than it has to be and this partial reopening will provide some relief for the thousands of motorists and local people whose lives have been disrupted. I can assure those people that I will ensure the team continues to work tirelessly in order to get this vital structure fully operational as soon as possible.”

Garrett Emmerson, Chief Operating Officer for Surface Transport at TfL said “Our engineers, contractors and suppliers have worked day and night during the Christmas period and beyond to enable us to partially reopen the flyover as quickly as possible. This should significantly reduce the traffic disruption many thousands of drivers have been experiencing since the flyover closed, and means that work to fully reopen the flyover will be completed well before the London 2012 Games.”

[Cudzoziemiec]

That does sound a little as if they're rushing to get it open for the Games even though it won't actually be up to full strength by then. There's bound to be extra traffic at that time, it would be a bit embarrassing for Boris if it collapsed under Olympic traffic. I wonder if they actually intend to reinstate the weight limit and just have cars use it then? Or maybe it will be one of the special Olympic official routes? 

[rogerzilla]

Surely the Army could knock something up in a weekend?  They used to build bridges to carry tanks in half a day.

[sas]

They probably could. Unfortunately there's a difference between an obedient highly trained tank driver and a motorist with phone in hand.

[Cudzoziemiec]

There was a pontoon bridge in Warsaw built by the army as a temporary/emergency measure just after WWII, which was finally replaced in 2002. I used to live very near it. It may well have had a weight limit though, I can't remember.

[Bledlow]

IIRC, the Hammersmith Flyover was built by the firm mostly (80%) owned by Ernest Marples, Minister of Transport at the time his ministry awarded his firm the contract.

He offloaded his shares when a fuss was made about a minister giving himself contracts - to his wife, with an option to buy them back at the same price when he left office.

[Tewdric]

IIRC, the Hammersmith Flyover was built by the firm mostly (80%) owned by Ernest Marples, Minister of Transport a

He was also the real butcher of branch line railways, appointing Beeching to do his dirty work.  It went relatively unnoticed that he had significant road-building interests.

[benborp]

The Lewisham Rail flyover was a temporary military structure built after the disaster in 1957. It's still in use today.

[phil d]

That does sound a little as if they're rushing to get it open for the Games even though it won't actually be up to full strength by then. There's bound to be extra traffic at that time, it would be a bit embarrassing for Boris if it collapsed under Olympic traffic. I wonder if they actually intend to reinstate the weight limit and just have cars use it then? Or maybe it will be one of the special Olympic official routes? 

It seems unlikely that if there were any risk of collapse that they would reopen it to even a single car.  Doesn't it?

[Biggsy]

Now open.  Email from TFL:

I am writing to let you know that the engineering works to enable the full re‑opening of the Hammersmith flyover has been completed ahead of schedule and the flyover is now open to all vehicles.

The works have involved the installation of concrete barriers as well as 22km of new cables within the structure to supplement the load capacity.

I apologise for any inconvenience you may have experienced during the works.

[Roadie]

It's not going back to 1 lane each way after the olympics is it?
I use that route a couple of times a week and it was a nightmare during the repairs

[benborp]

And now the M4 is closed over another elevated section.

http://www.bbc.co.uk/news/uk-england-london-18751083

[rogerzilla]

That has its own thread:

http://yacf.co.uk/forum/index.php?topic=61136.0

In Vroom because it's a motorway, and therefore not relevant to bikes, unless you're a certain S. Legg.