Safe Speed Forums

Update on real story which featured it originally in June. I was rather surprised to note they were on about putting slippery road signs rather than stopping using the stuff. In TRL's tests braking was increased by up to 40% in the dry! This is outrageous as clearly these road surfaces are not fit to be used. They can also take up to 18 months to bed in. In my opinion this surfacing technique should not be used anywhere unless the road can be aged in the process so it isn't slippery when new. If signs went up saying 'warning lethal road surface, don't expect to be able to stop' people might actually put pressure on the right people.

This crap road surface could explain the massive increase apparent excess speed accidents, which could be falsely attributed to the driver, when the road surface was at fault and made them take much longer to stop than expected thus upsetting the usual calculations.

I assume you're talking about Stone Mastic Asphalt?

If what I've heard about it is true, the stuff should never have been approved for road use.

Yep, DfT incompetence again - they were the ones instructing the TRL: "This product is gravel covered in some oily stuff; we won't bother to test it in the dry..."

It was referred to as thin coating something or other. Stone mastic asphalt might be another name for it. From the description of how it was made it sounds like the same stuff. The report was on about the government wanting to cover 60% of uk roads with this gunk before 2010 If anything they should be covering all the roads with the non skid surfacing rather than the lethal stuff. We pay enough in fuel taxes to pay for it.

If they couldn't be bothered to test it in the dry did they bother with other adverse weather conditions eg ice/snow etc?

I am just wondering whether it is worth contacting the local highways agency asking them whether they use it and whether in light of these serious safety concerns whether they are going to carry on using it.

Article in the local paper about a mysterious fatal wondering why a sensible rider still hit a range rover. Speed estimates put his speed at up to 65 mph but he still should have been able to stop according to an accident investigator. Don't know whether the road was resurfaced before the accident though. Local paper's comments method doesn't actually work which is rather infuriating as it means it is difficult to get in touch with the guy that is looking into it.

A chap on another forum managed to rear end someone one a recently resurfaced road. Another victim of this surface perhaps? He was driving a little close but the surface may have made it a much worse accident than it should have been.

Never mind SMA the real challenge at the moment is the Mollasses covered Salt that is being spread on the roads. This stuff is lethal making the roads as slippery as ice at temperatures well above freezing.

Absolute nightmare on the bike.

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Former Military Police Officer and accident investigator

When they eventually get round to bringing out the amendments (now looking to be 2007), CDM Regs will require Designers to consider the end user and fit for purpose.

Wonder if the Highways engineers are up to speed on thier CDM ??

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Gordon Brown saying I got the country into it's current economic mess so I'll get us out of it is the same as Bomber Harris nipping over to Dresden and offering to repair a few windows.

Chaos, panic and disorder - my work here is done.

http://www.wildcrafts.co.uk

SMA - stone mastic asphalt does have early life skid resistance problems there is no doubt about it.

I was amazed when I saw the bbc programme, we were putting it down on a major scheme in devon back in 97 and the issue was certainly known then.

DCC insisted on us gritting the road for the first x many months - not sure if this actually helped or not.

The problem is that with SMA the coarse aggregate is 'in the mix' and therefore the exposed surface is covered with slippery bitumen. This wears off but only after trafficking. This is opposed to say HRA (hot rolled asphalt) were the chips are rolled in afterwards.

Most thin surfacings (and there are many) are basically variations of SMA but each is a patented proprietry design owned by the various aggregate companies.

Why SMA? well its simple it lasts twice as long as HRA and the thin surfacings are clearly cleaper to lay.

SMA is here to stay and in my opinion is the best engineering solution. The challenge is to address the early life skid resistance.

It may be here to stay but it is banned on roads with a speed limit over 30mph in Ireland.

My whole estate has recently been resurfaced with what appears to be SMA. Certainly the first 2 weeks it was like driving on ice, entertaining as it is a quiet road but not particularly safe if you needed to stop.
Thats not my point though. During the course of the works all the houses received a little postcard from the contractor explaining that this technique would;
1,improve the road surface and ride quality, which if they bothered to fill the trenches in the road first would probably be true.
2, is a cost-effective and rapid form of imporevement, cheap and cheerful then!
3, would keep the road in a usable state for another 10-20 years without any further maintenance. Cost cutting and cheap (again)!
I supose on small quiet residential streets where speeds are generally low and accidents infrequent as a result this product is more than acceptable but on fast busy roads then the cost and disruption short term of replacing the surface is surely a price worth paying long term if safety and longevity were the real priorities, not just meeting some government target on road surfacing

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The police ARE the law, not ABOVE it!!!

Funnily enough, I was on a three day course on CDM and the upcoming changes the week before xmas!

But that is an interesting point concerning our responsibilities under CDM w.r.t. SMA.

Now if only I could get our Clients to carry out their duties...

Dougman, if you don't mind me asking, what do you do ??

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Gordon Brown saying I got the country into it's current economic mess so I'll get us out of it is the same as Bomber Harris nipping over to Dresden and offering to repair a few windows.

Chaos, panic and disorder - my work here is done.

http://www.wildcrafts.co.uk

Aren't the revised CDM regs also going to put more pressure on clients to fulfill their obligations?

As for SMA I don't know what the answer is but we're going to see more and more of it thats for sure.

In theory, the regs will be putting more emphasis on clients fulfulling thier duties and also consideration of the end user, but wether the HSE will actually enforce it remains to be seen, so far they have done very little with regards to clients.

They seem to have been targeting the Designers and Planning Supervisors (soon to be called Co-Ordinators). But with a lot in the construction industry it is very much client led and there is little incentive for clients to raise thier game

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Gordon Brown saying I got the country into it's current economic mess so I'll get us out of it is the same as Bomber Harris nipping over to Dresden and offering to repair a few windows.

Chaos, panic and disorder - my work here is done.

http://www.wildcrafts.co.uk

To save me explaining it all, I'll point you over here

Hope that works! [/url]

Another issue though with revised CDM...will the regs actually impact on the end user, surely they are what they say 'Construction, Design and Maintenance Regs.

If the road is not fit for purpose due to a design issue then surely the designer could be pursued through the courts for negligence?

Excuse my ignorance chaps but is this SMA you are talking about the beige coloured stuff they put down in the breaking zone for traffic lights and pedestrian crossings etc?

If so it seems to be getting ripped up by heavy traffic fairly quickly or at least it is in our area.

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Shooting is good for you and too good for some people.

Nope, that's something else.

SMA is a new road covering that is being used to resurface 'normal' sections of road. Unfortunately it's crap when first laid, possessing the grip of an ice rink under certain circumstances if my understanding is correct.

I remember seeing a TV prog about it about 6 months ago.

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Less Kodak, more Kojak.
In times of deceit, telling the truth is a revolutionary act.

Actually the application of anti skid surfacing at junctions and roundabouts etc is one of the solutions to SMA early life skid resistance.

would cost a few quid to coat our entire network with it though.

So what does this SMA look like and how would we know we were on it?

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Shooting is good for you and too good for some people.