According to a paper written by Clay Gabler of Virginia Tech titled “The Risk of Fatality in Motorcycle Crashes with Roadside Barriers,” in 2005 for the first time in the United States, motorcycle riders suffered more fatalities (224) than the passengers of cars (171) or any other single vehicle type involved in a guardrail collision. In terms of fatalities per registered vehicle, motorcycle riders are dramatically overrepresented in number of fatalities resulting from guardrail impacts. In the
Traditionally motorcyclist safety has not been taken seriously into consideration when developing longitudinal barrier testing criteria.
A variety of products have been developed to protect motorcyclists who impact longitudinal barriers. Most of these products, many of which come from
I have heard some experts say that they believe that a motorcyclist impacting a concrete barrier, or a steel barrier or a cable barrier system will die. It is just a question of “how dead will you be, 100% or 140% or 160%?” However, the real debate comes from the motorcyclists complaining specifically about the cable barrier systems. They refer to these cable barriers as “cheese cutters.” They cite an accident in October of 2007 in
Some road experts believe the cable barrier actually is safer for motorcyclists when it is impacted. They explain that the cable barrier steel posts are more likely to fracture when impacted. They also claim the cable barrier will be placed further away from the road because of the working width of the cable barrier.
Both sides of this issue need to be explored and this issue needs to be resolved. The question is simple; are cable barrier systems more dangerous for motorcyclists than steel barriers or cable barriers, are they safer, or are they the same? Your comments are welcomed on this site.
The issue of motorcycle safety and longitudinal barriers will be the focus topic at the AFB 20 (2) Roadside Safety International Research Subcommittee meeting at TRB in
10 comments:
With reference to wire-rope barriers, they are fatal for motorcyclists. A recent study in Scotland showed that out of 7 impacts last year there were 7 motorcyclist fatalities. That’s 100%. They have been banned in the Netherlands and will probably be banned in Sweden soon. Following pressure from the BMF, the Highways Agency in the UK has also banned wire-rope barriers along its network.
Other barriers are also very dangerous to motorcyclists. Posts in particular have been shown to have serious issues for motorcyclists. Unfortunately, the state of research is not that good. I can categorically state, though, that not all accidents involving road restraints are fatal and therefore the argument that motorcyclists don’t need to be taken into account is specious and based on prejudice. At a recent EuroRAP meeting a supposed expert stated that all motorcycle accidents over 20mph were fatal which goes to show how much expertise in this area is available.
Spain is the most advanced county with regards to barriers. They have two standards for barriers both of which have been tested for motorcyclists. Standard barriers are fitted to roads which have low numbers of motorcycle accidents. The higher spec barriers are fitted to roads with higher numbers of motorcycle accidents. This is in contrast with the rest of the world where there is usually one specification for all roads.
In short, barriers have not been designed to take into account motorcyclists and the research in this area is not very good. The BMF and other motorcycle organisations such as FEMA usually support barrier systems without posts.
Chris Hodder
British Motorcyclists Federation
In Brazil, the National Traffic Department - DENATRAN is working to release an resolution (traffic law) to implement additional protection on the road side barreir for motorcycles drivers. The number of deaths on the guardrail impacts for motorcycles drivers are growing in an exponential way. We are working to help Denatran to identify international standards regarding this kind of protection.
Eugenio Brunheroto
Barrier Systems Brasil
eugenio@lindsay.com.br
The US Federal Highway Administration will be looking for more in-depth data on motorcyclist crashes into roadside and median barriers to determine how effective motorcycle - friendly barriers would be. We have seen the European test videos of various designs and retrofits and need to be sure these barriers are addressing the actual mechanics of motorcyclist impacts into barriers in the US before we consider their use. Nick Artimovich, FHWA Office of Safety Design
I feel it necessary to provide some balance to the debate regarding motorcycles and, in this case, just to bring to light the facts about the NZ crash since reading the article presents only one side - and an emotionally compelling on at that. The facts of the accident that follow were gained from investigators whom my sources interviewed. The incident occurred about 3am on a straight section of motorway just south of Auckland . Transit NZ have no hard evidence , but it seems 3 motorcyclists were racing each other at speeds between 150 and 200 km/hr . The dead rider was also wearing a crash helmet with a dark tinted visor . From the point at which he fell off the m/cycle to the point where the body came to rest was 330 metres , hence Transit believes that the estimates of 150 - 200 km/hr seem to be realistic . The driver flattened serveral posts before becoming wedged under the ropes at an anchor, but it is believed the posts were the cause of the body severing because the driver was on the ground the whole time. It was also noted that the bikes' front forks were sheared off. The driver had a reputation among police for doing wheelies and it is believe the forks may have failed as a result of metal fatigue from the cumulative shock load of landing a wheelie.
The road safety community must consider all vehicle types in evaluating barrier applications, but there is a limit and one must consider to what degree can agencies go to protect a driver who takes such risks.
Regarding the comment from Chris Hodder that "wire-rope barriers will probably be banned in Sweden soon" I must state that there are no such plans. I agree that barrier posts are dangerous but that is regardless of the type of barrier. We have not seen any proof that wire-rope barriers are more dangerous than other types of barriers with posts.
When we deal with pedestrian impacts we can protect about 90% when they are hit by a car at 30 km/h. At 50 km/h about 90% get fatal injuries. Here we are talking about being hit by a large object and not a narrow post which is more aggressive. Pedestrians and motorcyclists belong to the same category "UNPROTECTED ROAD USERS" and we have to remember that when we talk about the countermeasures. We also have to remember that the barriers are installed in order to protect something that is worse to hit than the barrier.
Thomas Turbell
VTI Sweden
With reference to wire-rope barriers, they are fatal for motorcyclists. A recent study in Scotland showed that out of 7 impacts last year there were 7 motorcyclist fatalities. That’s 100%. They have been banned in the Netherlands and will probably be banned in Sweden soon. Following pressure from the BMF, the Highways Agency in the UK has also banned wire-rope barriers along its network.
Other barriers are also very dangerous to motorcyclists. Posts in particular have been shown to have serious issues for motorcyclists. Unfortunately, the state of research is not that good. I can categorically state, though, that not all accidents involving road restraints are fatal and therefore the argument that motorcyclists don’t need to be taken into account is specious and based on prejudice. At a recent EuroRAP meeting a supposed expert stated that all motorcycle accidents over 20mph were fatal which goes to show how much expertise in this area is available.
Spain is the most advanced county with regards to barriers. They have two standards for barriers both of which have been tested for motorcyclists. Standard barriers are fitted to roads which have low numbers of motorcycle accidents. The higher spec barriers are fitted to roads with higher numbers of motorcycle accidents. This is in contrast with the rest of the world where there is usually one specification for all roads.
In short, barriers have not been designed to take into account motorcyclists and the research in this area is not very good. The BMF and other motorcycle organisations such as FEMA usually support barrier systems without posts.”
British Motorcyclists Federation
Road Users' Alliance member
A CASS cable median system has been implemented in 3.5 km of a high speed (80 k/h speed limit) 6 lane urban arterial in Santiago, Chile.
In one 30 month period over 120 auto and truck impacts with the barrier were documented with No Fatal crashes, No serious injuries and no Median Crossovers. For that matter, none of the minor injuries were attributable to the barrier system, but rather to secondary crashes. This compares with numerous fatalities from the crossover accidents prior to installing the system.
During that same period there were three motorcycle crashes involving the barrier resulting in 1 Fatality, one minor injury and one property damage only event. The one fatal crash involved a young man speeding at over 140 km/h who sideswiped a car, fell onto the pavement where his helmet came apart and according to police was probably dead when his body ran into one of the cable system posts which first tore off his arm and then part of his skull.
One of the advantageous of the cable barrier systems is that they are easily repaired, in most cases in minutes and so minimizing traffic delays and for the system commented above the original cables are still in place, providing protection from fixed objects and limiting crossover situations until full repairs could be accomplished.
As a road safety professional with many years of experience I am concerned that because of a few gruesome and lamentable accidents involving motorcyclists, a very effective and safe barrier system is being called into question.
In my professional judgment, the cable systems are safer for motorcycles because the posts are less rigid and they are designed to yield upon impact.
The motorcycle industry needs to objectively investigate the accidents that they claim are aggravated by wire-rope barriers. I know that they will find that the "cookie cutter" effect is not caused by cables; rather it is caused by the posts and aggravated by excessive speed.
The research done in Spain is not for motorcycles, it was for dummies that had theoretically "separated" from their vehicle and the elements added to the barriers in Spain do not result in a "higher" spec barrier. Rather they result in a barrier that under limited circumstances will be less aggressive to motorcycle riders and passengers that have laid their bike down because they lost control of the vehicle on a curve.
The modified barrier is a more costly barrier, and one which I fear will result in poorer performance for normal situations. The skirts being fitted to existing barriers may result in more cars going over the top of the barrier.
Finally, I agree that there has been very little research in the area of motorcyclists and crash safety for these vehicles beyond the use of helmets and the quality of the helmets. We should consider that there is very little, if any, testing of collisions between motorcycles, or for that matter between motorcycles and 4 wheel vehicles.
Greg Speier P.E.
Highway Safety Specialist
Speier Road Safety Solutions
IRF Member Company
I think my greatest concern is the involvement rate of motorcycles (MCs) in traffic barrier crashes. Some of the numbers currently being cited indicate a very high involvement rate for MCs in fatal barrier crashes. I don't know where those numbers come from, but a critical first step in addressing this issue is to make sure we know the extent of the problem, and I am concerned that we do not know enough at the present time.
In the mid 1980s, we conducted a number of in-service traffic barrier performance studies in the NYSDOT. One of those studies examined all barrier crashes on the NY state highway system over the period 7/1/82 - 6/30/83. That study is described in TRR 1065. However, the interesting part of the results - MC crashes - is contained in a 1985 ASCE Publication "Effectiveness of Highway Safety Features."
Those numbers show that MCs were involved in only 83 of the 3302 barrier crashes reported, or only about 2 1/2 %. However, 7 of those MC crashes resulted in a fatality, or 16 % of all fatal barrier crashes. Overall, fatalities resulted in 44 of the 3302 crashes, or just over 1% overall. While this certainly indicates motorcycle riders are at much greater risk than occupants of other vehicles, these numbers are not as alarming overall as the numbers we saw presented this summer in South Dakota.
Some of this difference may relate to the age of my data - there were certainly fewer MCs on the road in the mid 1980s than currently. Further, NY may have a lower proportion of MCs in the traffic stream than some other states, and MCs here are ridden only about half the year, due to our winter conditions.
In response to the comments by Chris Hodder I should correct a few points;
Firstly the 7 casualties in the Scottish study were fatal or seriously injured, they were not all fatally injured.
Secondly, the Highways Agency has not and, as far as I am aware, has no plans to, ban the use of wire rope safety fencing.
I should also add that motorcyclist protection is now to be considered by planners when designing new schemes due to the new requirements of the Highways Agency' safety barriers standard, TD19/06.
A.
Having ANY median barrier or good separation of flows is better than none for the whole population.
B.
Selection and placement of barriers needs more careful research. Motorcyclists have been mostly ignored in designs of current barriers. Barriers often present a greater injury risk than no-barrier
C.
Roadside engineering remains in the 1930's, while car occupants are protected with astounding engineering technology. Yet, over 40% of car occupant casualties are from roadside objects, including barriers. People make mistakes, so make the roadsides more forgiving, like cars are now.
D.
Wire Rope Barriers will not "flex" when impacted by a rider. The posts are rigid, thin Z-profile or dog-bone profile. The design specifications require a vehicle of at least 500kg before effective flexing occurs.
This is advertising "spin", useful to sales where ignorance prevails.
See this paper:
"The Emerging Risk of Fatal Motorcycle Crashes with Guardrails" (2007)
Hampton C. Gabler
Associate Professor
Department of Mechanical Engineering
Virginia Tech Center for Injury Biomechanics
http://www.me.vt.edu/gabler/publications/TRB-07-3456-Motorcycles-Final.pdf
The bibliography of Gabler's ppaper is an excellent resource to get to facts and away from opinions.
Item 5 of this bibliography was funded by riders in NSW, Australia because our government would not fund motorcycle crash research at all. A copy can be found on our website:-
http://www.roadsafety.mccofnsw.org.au/a/63.html
I also commend you to Item 6 of Gabler's bibliography.
Yes, it's an emotive issue for riders. Does that mean it should be disregarded?
Go to this link for our latest (yesterday) fatal WRB chop-up in Tasmania. http://www.thewest.com.au/aapstory.aspx?StoryName=449440
- Guy - Australia
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