Looking at the final positions of the vehicles, I reckon that the unlucky Merc occupants were just a few feet from safety. The crash barrier has prevented the truck going over it, but it has bent allowing the truck to go across three lanes of the opposite carriageway. If the truck had gone over/through the barrier, the carnage would have been a lot worse.
www.dailymail.co.uk/news/article-1386808
Last edited by: Suppose on Sat 14 May 11 at 09:45
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Looks like the barrier designers need to go back to the drawing board or was it bad installation.
I assumed the whole point of these were to prevent accidents like this happening.
Interestingly, a lot of the M62 by me, now has shaped concrete central barriers. I wonder if these would have prevented this happening.
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extremely sad for all the families involved ! this just go to show how the concrete centre barriers need to be installed everywhere.
Thoughts should go to the families involved. Horrendous
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>> Looks like the barrier designers need to go back to the drawing board or was
>> it bad installation.
Yeah, that's a faulty Barrier install, the steel ribbon is in tact and hasn't broken ( Working as designed), but has stripped from its supports ( not as designed )
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>> that's a faulty Barrier install, the steel ribbon is intact and hasn't broken ( Working as designed),
>> but has stripped from its supports ( not as designed )
ISTR standard single Armco barrier can only withstand a direct perpendicular hit of 1.3 tonnes - more at an oblique angle obviously but not enough to prevent an HGV crossover incident such as this.
Terribly sad, but thankfully extremely rare - hence why it's made the news.
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given the length of armco it has behind it, it was a very oblique angle, and should have guided the lorry back onto its own carriageway.
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>> given the length of armco it has behind it, it was a very oblique angle, and should have guided the lorry
>> back onto its own carriageway.
Agreed, there's clearly something amiss with the barrier assembly here. The barrier itself appears in the pictures to be well patinated, from memory that stretch of the M5 is one of the oldest (a quick check on Wiki shows it to be 41 years old) so fatigue could be an issue. However, I get the feeling there could be a "sweet" angle at which the momentum of the lorry could overcome the securing force in the barrier fixings without significantly slowing or deflecting the lorry, and once it's done one fixing a large number will follow in the same vein.
I notice the vertical posts are still standing. The current method of fixing them to the ground involves expanding foam (which doesn't seem to be evident in the pictures), so it can be assumed the barrier here dates back some years.
Last edited by: Dave_TDCi on Sat 14 May 11 at 22:16
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Dave_TDCi>>The barrier itself appears in the pictures to be well patinated, from memory
>>that stretch of the M5 is one of the oldest (a quick check on Wiki shows it to be 41 years
>>old) so fatigue could be an issue.
No, I guarantee that fatigue is not an issue as this is the first time it has been used.
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A metal crash barrier works by acting as a giant rubber band which deforms around the front of the vehicle which effectively stops it rebounding into the road. The posts which hold it are purely to support it at the correct height above the road surface. They perform no other function and are designed to come away from the barrier.
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But its not designed to allow a truck across the other carriageway, taking 50 yards of in-tact steel ribbon with it. I have never seen that before, seen it flattened over, seen 4x4s rolled over it, and seen it bent.
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crash test goes wrong
www.youtube.com/watch?v=Fh8VM-nfPo8
car bounces off barrier on to following car
www.youtube.com/watch?v=Q7ydXgLgK3Q
truck crash near Ipswich
www.youtube.com/watch?v=NEDusPbd5n0
new concrete barriers - by Vicky B Henderson
www.youtube.com/watch?v=6fD3UMhTWWw
West Yorks Police video of truck accident on M621
www.youtube.com/watch?v=l_eiP8sk_KQ
finally - good driving by barrier delivery driver
www.youtube.com/watch?v=WV7rgWGj-ZM
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It has actually worked now I described but obviously the impact and angle that the barrier has been struck is too great. Remember the main aim of a metal crash barrier is to stop a vehicle rebounding across carriageway in which it is travelling. To prevent "crossover' incidents you need a concrete barrier.
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>> Remember the main aim of a metal crash barrier is to stop a vehicle rebounding across carriageway in which it is travelling.
What's the thinking behind that?
Surely a crossover is more dangerous, due to the fact of being a head-on collision?
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I thought the idea of the crash barrier was to guide the errant vehicle back into its own carriageway, traveling the same way.
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>> I thought the idea of the crash barrier was to guide the errant vehicle back
>> into its own carriageway, traveling the same way.
>>
Exactly what I thought Z....
surely its better for an out of control vehicle to be mixing it with other traffic travelling the same direction?
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Those armco jobs usually do the trick with cars and vans. But I do remember a case a couple of years back where the metal strips were fitted the wrong way round and one detached on impact impaling a driver or passenger.
The shaped concrete barriers, which one assumes are more expensive, will obviously be better at preventing crossovers like the one in the OP. But truck wheels can climb them and flip the truck over.
In any case these barriers, however made, are there as a long-stop, an expedient of last resort. When they come into play whatever it is has already happened. Hundred per cent safety can't be guaranteed on a motorway with traffic on it if some jerk insists on losing control of their vehicle, stopping in the dark in the outside lane or anything like that.
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'I thought the idea of the crash barrier was to guide the errant vehicle back
into its own carriageway, traveling the same way. '
Yes,but without rebounding across the carriageway i.e the vehicle is retained in the loop of the crash barrier, which dissipates the energy by distortion along its length. The crash barrier in question has effectively done that but because,of the direction and force of impact has carried across the opposite carriageway.
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Maybe what we really need, is a ribbon type crash barrier, but with a concrete wall behind it?
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Two women killed on M5 - truck hits Merc head on - MrTee43
