New type crash barriers - M7

Silvera

Anybody notice the new type of crash barrier on the Kildare By-Pass ?

I was on the new stretch of the M7 today and noticed that the crash barrier was the new type (also on trial in Australia) which incorporates poles, about 5ft apart, with three strands of wire rope between each pole.


Looks similar to this -

(Swedish Trials)

silverside

I don't think the bikers will like this!

Didn't the NRA promise that all new roads would have appropriate crash barriers which was taken to mean the deformable railings?

Maybe they are just temporary? Someone tell us whats happening? Victor?

Samson

I dare say the wire crash barriers are considerably cheaper than armco barriers.

And if a biker or two gets sliced in half?
Well, I'm sure the NRA et al are of the view that a few chopped up bikers is a cost they are prepared to pay (after all, they have saved a bit of money).
Similar to their view on the "chicken wire" issue for so long!

Johnmb

Originally posted by Samson
Similar to their view on the "chicken wire" issue for so long!

I wish people would lay off them over the chicken wire. I have been driving on the motorways, and dual carraigeways, that use it for years now, and I have to say that they are 100% effective from my experience. Not once have I been hit by a stray chicken!

Capt'n Midnight

If I remember correctly (saw a prog on telly a long time ago) an artic or short wheel base rigid will pull the wires out more than a car. ie. there is a chance it would actually end up [temporarly while the wires were stretched] in the overtaking lane on the other side of the carraige way. An that's why solid barriers were installed in the 60's....

Ok I don't know if this is a newer better system BUT the kenetic energy of a one tonne car at 70mph is a lot less than an overloaded truck breaking the limit (a daily event ?) which is what happens in the real world - you have to take into account the worst case likely senario.

Also is there any chance the vehicle will get bounced back into the lane it just left when the wires unstretch ??

Johnmb

Originally posted by Capt'n Midnight
Also is there any chance the vehicle will get bounced back into the lane it just left ??

On a more serious note, I don't think it is as much of a problem if it bounces back as it is if it goes through. If it bounces back, the forward momentum will keep it going in the same direction as the traffic, and any drivers behind would have seen it go off and would have a good chance of being able to react. If it goes through, the forward momentum will take it in the opposite direction to the traffic, and the first any drivers will know of it is as it comes crashing towards them, giving them much less time to react. I do believe that the bouncing back is the lesser of two evils, and gives the affected drivers the best chance of survival. It doesn't make sense to me that the NRA would use crap barriers that allow vechicles to cross the meridian in order to avoid a few bouncing back.

Victor

Originally posted by silverside
Maybe they are just temporary? Someone tell us whats happening? Victor?

I don't know, first I heard about them was Thursday or so. I think they are better than nothing and what people tend to forget is that motorways are immensely safer (even without barriers) than ordinary roads per vehicle km, the M50 is the second safest national road in the country (not first safest, only because the safest one recorded no accidents last year). The over taking lane, lack of at grade junctions, the median and good visibility all contribute.

I'm not convinced on this, but the cost of installing full crash barriers everywhere **may** be better spent on upgrading specific dangerous sections of road **first**.

Andrew Duffy

I don't think the bikers will like this!

Re Armco barriers - aren't they lethal to bikers aswell? Is there a good barrier type for bikers?

Capt'n Midnight

Originally posted by Johnmb
I do believe that the bouncing back is the lesser of two evils, and gives the affected drivers the best chance of survival.

Yes it is the lesser of two evils - but there are alternatives..

The problem is that the barrier should not act like a spring, storing energy from the first impact and then releasing it to create a possible second accident. There are several ways of doing this - use gravel traps to slow the vehicle down , have a barrier that crumples, a rigid barrier (then you are reliant on the crumple zones in the vehicle) plastic drums filled with water (if you leave the top open they will be self filling ) as in the states. You could use hedges - but only if the whole width of the meridian was covered by them - a single hedge only had sound adsorbtion and cosmetic uses.

I'm not convinced on this, but the cost of installing full crash barriers everywhere **may** be better spent on upgrading specific dangerous sections of road **first**.

Agree that the money should be spent where it will bring most benefit. Note: Public transport is far safer than private motoring when measured by passenger journies esp. if you take into account it's impact on other road users..

Victor

Originally posted by Capt'n Midnight
a single hedge only had sound adsorbtion and cosmetic uses.

Primary function of the hedges is anti-glare.

Capt'n Midnight

Originally posted by Victor
Primary function of the hedges is anti-glare.

Well that's sorta cosmetic and vegetation does reduce sound a tiny bit (and removes some dust) - even so a single hedge doesn't block all the light.

Anyway I thought we are due a third lane on the M50 so they would want something substantial in between.

Victor

Originally posted by Capt'n Midnight
Anyway I thought we are due a third lane on the M50 so they would want something substantial in between.

Yes, they will be going in the existing grass meiadn so full barriers will be put in place.

Silvera

In today's Irish Independent, a letter writer said she was appalled to see the new safety barriers on the Kildare-Bypass.
She said they are known as the 'human cheese cutters' because of the injuries they can inflict on motorcyclist's.
She calls for the barriers to be replaced with a more "motorcyle-friendly alternative".


I suspect that her call will fall on deaf ears in the Dept of Transport.

an_taoiseach

I guess MAG are less than delighted with this latest move to reduce the number of motorcyclists ( is the the first effort by the NRA at a targetted cul of road users ? )

http://autos.groups.yahoo.com/group/motorcycle-ireland/


An T

Samson

Originally posted by Johnmb
I wish people would lay off them over the chicken wire. I have been driving on the motorways, and dual carraigeways, that use it for years now, and I have to say that they are 100% effective from my experience. Not once have I been hit by a stray chicken!

Touché.