I am refering to the sections of Armco that are on the side dual carriageways and motorways that stop you dropping off bridges or into railwaylines that are below the carriage way.
They used to start with a lump of concrete in the ground, slope up to the usual operating height go along till the hazard has passed then slope down into another lump of concrete.
But recently (well, the last couple of months) I have noticed that instead of starting from the ground, they are starting at the operatring height with a board with orange stripes to tell you its there.
Surely and coming together with a car is going to be worse that with the slopey start?
A friend said that maybe they are cusioned with a crumple zone, but on closer inspection whilst flying past, they look like a flat board.
Anyone know the reasoning behind it?
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Aim low, expect nothing & dont be disappointed
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to stop another great heck i would have thought, as otherwise you could ride up the armco and land yourself on a train?
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This is a question I'd been meaning to post since these things appeared a year or so ago. It's present in far more places than just wher Armco protects rail overbridges.
I suspect the answer is that the old design was capable of flipping a car over whereas the new thingy looks like a buffer ans will absorb impact.
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If it works properly an Armco-type barrier should deflect a vehicle fairly gently back into the carriageway without turning it over. Those ramp-style ends were capable of turning a car over.
There used to be a barrier made of steel cables. I think they stopped using it because it was lethal to motorcyclists.
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I agree with Lud.
I once pulled a woman and her 2 children out of their car which was on it's roof blocking one lane of a dual carriage way.
She had turned to sort the kids out, strayed into the path of the armco and just shot up the gradient and it flew the car into the air and over onto it's roof.
Thankfully everyone was ok except for lots of screaming and crying from the kids.
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>I once pulled a woman and her 2 children out of their car which was on it's roof blocking one >lane of a dual carriage way.
Funny that. I passed an almost duplicate situation on Wednesday night on the A3 at New Maldon.
Single car, hit the armco and was upside down in the middle of the southbound carriageway. Very messy - bit of car everywhere.
A good reminder to anyone who thinks that A3 50mph speed limit is too slow!
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TourVanMan TM < Ex RF >
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I imagine you can invert a car on armco at 30 TVM. And of course you can avoid the armco altogether at 70.
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Funny that. I passed an almost duplicate situation on Wednesday night on the A3 at New Maldon.
snipquote
I saw this too, TVM, on our way back from a very pleasant Thai meal in Wimbledon Village. I thought the car was a Clio, and SWMBO thought she saw a number of youths hanging around. So perhaps they were going faster than 50 (not that one should stereotype!!)
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To answer this you need to know why armco is there. Its not as you may think to protect you from harm, Its there to protect others from you harming them. Armco is flexible, designed to gather you up, keep you roughly going the right way, on the right carriageway, and in doing so hopefully not cause too much damage or injuries to any innocent party.
The concrete skijump, if hit, used to flick cars up and over, and you could end up going anywhere ontop of anyone.
So its better (for eveyone else) for you to brought to a crashing halt if you hit one end on.
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TourVanMan TM < Ex RF >
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These new things are in no way buffers. They aren't thick enough.
I suppose it is a no win situation, either the vehicle is span into a river/train track or the vehicle is speared through with the armco.
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Aim low, expect nothing & dont be disappointed
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Reminds me of the journey we had, once, early hours Sunday morning.
Just pulled off the M25 onto M1 North, clear road & when this was when we had the Jaguar, so was travelling at a comfortable pace, on empty road. & then from 'nowhere', behind us at a considerable speed, were the blues n 2's.
Expecting a friendly chat, with an officer, I was pleased that they shot past me, without stopping.
When we approached junction 9, the reason for their urgency, was apparent. An XR3, driver, had managed to get his nearside wheels, up the Armco, between the off slip & lane 1, riden, about 100' along & remained balanced upon it.
Now he wouldn't do that easily, with these latest style barriers, would he!!?
VB
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I thought this had been discussed before, but can't find it.
They're deformable crush barriers, to stop vehicles being somersaulted into an aerial spin.
With their deformation, and the colliding vehicle's, they reduce the likelihood of a vehicle being sent uncontrollably off anywhere else.
If you think they're short, look at the deformable crush areas on F1 cars. They seem to work at anything up to 200MPH. Ask Mansell, Kubica.............etc.
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I thought this had been discussed before but can't find it.
This thread?
www.honestjohn.co.uk/forum/post/index.htm?v=e&t=50...3
(Sorry mods, don't know how to shorten)
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One mans junk is another mans treasure
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Re wire barriers; Bro in Law (Civil engineer) told me they're useful on high cross country routes to prevent snow drift build up. I'm sure they have other benefits too, but, as mentioned, not two wheel friendly. I wondered about cost, and found this from Hansard (albeit 2001)
Single sided corrugated steel barriers cost between £28k and £37k per kilometre, with the difference being accounted for by both the frequency of supports and the type of foundations used.
Steel wire rope safety barriers cost between £13k to £21k per kilometre, again with the difference being accounted for by both the frequency of supports and the type of foundations used.
Concrete barriers (operating at the same level of containment as both corrugated steel and steel wire rope barriers) cost approximately £45k per kilometre.
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Tim{P}
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(Sorry mods don't know how to shorten)
That one isn't overly long. There is however a Sticky at the top of this page called "TinyURL Shortcut Link" which will shorten a weblink for you, and all you then need to do is paste the shortened link.
DD.
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