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A Type of Road Junction that Kills Cyclists

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Re: A Type of Road Junction that Kills Cyclists

#401

Post by lsllc »

u801e wrote: post #285
mrb wrote: post #69

Earlier quoted context omitted.

« make it a 4-way stop » You may be unaware, but 4-way stop signs are very uncommon outside of the US. In fact, in the UK they have always been formally prohibited by the Department for Transport in 2002. As a European driver, I discovered the existence of 4-way stop signs when I moved to the US, and I have always found them dangerous in a counter intuitive way: drivers are so used to 4-way stop intersections, that t…

The other thing about 4-way stop intersections in the US is that the right-of-way rules when two vehicles arrive at the intersection at the same time is not quite what one would expect. That is, the vehicle to the right has the right of way. If the intersection was controlled by a roundabout, then the vehicle to the left would have the right of way.

In the US right-of-way for a 4-way stop is order of arrival, with yield to your right if you arrived at the stop line at the same time as someone else.

https://en.wikipedia.org/wiki/All-way_stop#Operation

In general it works fairly well even in areas notorious for bad driving (although sometimes people steal a turn, I've never seen someone blow right through one, even late at night).

Roundabouts are different. It's a one-way street that goes in a counter-clockwise circle, so naturally you if you are joining (effectively taking a right turn onto it) you must yield to traffic already on the roadway (that would be traffic coming from your left) as you would when turning right onto any street. Once you are on it, you now have right of way.

4-way stops are more deterministic, whereas traffic can get "starved" trying to enter a roundabout. However, you always must stop at a 4-way (even if it's a rolling stop), whereas you can blast through a roundabout if there's no-one to yield to.

Re: A Type of Road Junction that Kills Cyclists

#402

Post by brewdad »

pc86 wrote: post #375
NoGravitas wrote: post #334

Earlier quoted context omitted.

In most of the US (it varies by state), moped riders (where mopeds are generally defined as motorcycles below a certain engine capacity and top speed, often 30 or 40 mph) do not need a license.

I think having to ride a moped is a sufficient disincentive.

You're being silly, but this does impact the fastest growing segment of new bicycle riders: e-bikes. Right now, most states classify them as mopeds and may or may not require licensing accordingly, usually not. I don't know if there are any stats yet, since they are relatively new, but these e-bikes seem to me more dangerous in the hands of inexperienced riders than a traditional bike.

Re: A Type of Road Junction that Kills Cyclists

#403

Post by ajmurmann »

Piskvorrr wrote: post #156
larkeith wrote: post #106

Earlier quoted context omitted.

Having lived near a very similar intersection, also with frequent accidents (it has a 2-way stop with heavy 50-70 mph cross-traffic and frequent left turns, depending on the time of day), cost may be a significant portion of the reason; a neighborhood campaign to replace the 2-way stop with a traffic light fell through due to a >$1 million price tag for adding a light to a countryside road, and it's doubtful a rounda…

Anecdata: fixing frequent accident sites (e.g. 70 kph main road x 50 kph access roads) with traffic lights reduces minor accidents, but there was a major accident on one of them just recently...because "traffic lights be damned, nobody ever comes out that road anyw-BOOM." Traffic lights are a discretionary access control mechanism ("ignore at your discretion"), roundabout is a mandatory access control mechanism.

I wonder if that happened because the traffic light was just on a timer rather than taking actual traffic in account. If the smaller road hardly ever sees traffic the light would be red very infrequently and getting your attention when red.

Re: A Type of Road Junction that Kills Cyclists

#404

Post by beobab »

bertil wrote: post #384
ygra wrote: post #348

Earlier quoted context omitted.

Interestingly I've become a much better cyclist after obtaining my driver's license. It made me very aware of the fact that you can't see anything from cars (compared to the elevated and pillar-free view from a bike) so you have to be aware of that fact as a cyclist and react accordingly. Some things cyclists do without thinking much are stupidly dangerous and I think this often is the result of cyclists and drivers…

> you can't see anything from cars This is a very important difference and that’s the main reason I yearn for self-driving cars. Current vehicles are horrible to see where you are driving and drivers are in denial about it. At least, when you have engineers trying to represent a scene, they gut reaction is “No way I am dealing with such a slim view, I”m putting the camera where it can see what’s happening.”

The amount of times whilst pulling out of my driveway that I've thought "I wish I had a cameras pointing left and right from about where my indicators are" is quite large.

It's always worse when large vans are parked up and down the road so visibility is obscured.

Re: A Type of Road Junction that Kills Cyclists

#405

Post by u801e »

lsllc wrote: post #401
u801e wrote: post #285

Earlier quoted context omitted.

The other thing about 4-way stop intersections in the US is that the right-of-way rules when two vehicles arrive at the intersection at the same time is not quite what one would expect. That is, the vehicle to the right has the right of way. If the intersection was controlled by a roundabout, then the vehicle to the left would have the right of way.

In the US right-of-way for a 4-way stop is order of arrival, with yield to your right if you arrived at the stop line at the same time as someone else. https://en.wikipedia.org/wiki/All-way_stop#Operation In general it works fairly well even in areas notorious for bad driving (although sometimes people steal a turn, I've never seen someone blow right through one, even late at night). Roundabouts are different. It's a…

> In general [4-way stop] works fairly well

If you're not considering intersection throughput, then that may be true, but 4-way stops are one of the worst forms of intersection control when there's even a moderate amount of traffic.

> Roundabouts are different.

Of course, but what I was implying when I made my post is that a 4-way stop sign controlled intersection right-of-way rule is unusual compared to most traffic situations where one has to yield the right of way. At a yield sign, one typically yields to traffic coming from the driver's left. When entering a highway, one yields to traffic on their left. When making a right turn on red, one yields to traffic on their left after coming to a full stop.

Only when coming to a 4-way stop are the right-of-way rules reversed it seems.

> whereas traffic can get "starved" trying to enter a roundabout.

One thing that's done in the UK is to add traffic lights at the entrances to busy roundabouts. When traffic gets heavy, the activate the traffic lights to regulate traffic flow to prevent the starvation scenario that you mention. To me, that's the best of both worlds where one isn't legally required to stop even when there's no traffic approaching.

Re: A Type of Road Junction that Kills Cyclists

#407

Post by brewdad »

Svip wrote: post #181
TomMarius wrote: post #173

Earlier quoted context omitted.

The drivers shouldn't be punished for bad design of the road. A separate bike road should be constructed.

Indeed. The main type of accident involving cyclists in Denmark are so called 'right turn accidents', where a lorry turning right at a junction hits a cyclists because they are in their blind spot. This obviously happens exclusively in cities. The media has made a big deal about how tragic it is for the cyclists - which it is, but much less about how tragic it is for the driver. Remember, it's not like drivers want t…

You need to build the intersections properly though. My city, in the NW US, built a beautiful separated multiuse path alongside a 50mph road. The trouble comes at the southern end where two 50mph roads intersect and the separated bikeway turns into a standard on-road bike lane on the other side. This also happens to be the highest traffic volume intersection in my city of 100,000.

The intersection is designed so right turning cars can make the turn at about 15-25mph when they have the green. The same green that the cyclists have. Cyclists must wait at a position that puts them slightly behind the right turning driver and the design simply doesn't allow a cyclist to inch forward enough to change that. If you were designing an intersection that will get cyclists killed, this is how you would do it.

My approach is to stop at the green light and hit the pedestrian "beg button" and wait for the walk signal on the next light cycle (a minimum 2 minute wait). This is still no guarantee that drivers will actually yield to me, but at least it gives me a chance to be seen. Even waiting, and having the walk signal and right of way, drivers get irrationally angry at having to wait a few seconds for me to cross. A few don't wait and swing wide right in front of my path. Fun Times.

Re: A Type of Road Junction that Kills Cyclists

#408

Post by u801e »

talldan wrote: post #327
u801e wrote: post #274

Earlier quoted context omitted.

> The highway code says that cyclists should stay to the left. The uniform vehicle code (which is the basis of many state road rules in the US) states the following: >> Any person operating a bicycle... shall ride as close as practicable to the right-hand curb or edge of the roadway except under any of the following situations >> [...] >> When reasonably necessary to avoid conditions including [...] substandard width…

I completely agree. There are similar rules over here about leaving a gap to the kerb, and that there should also be a gap left by overtaking vehicles. Both are often not observed. Here's the (brief) rules for roundabouts: http://www.highwaycodeuk.co.uk/rules-for-cyclists-roundabout... Most cycling proficiency courses here in the UK will tell cyclists to ride more centrally when in a narrow lane, which is good advice…

> It gets a bit fuzzy though when there's a cycle lane provided.

A lot of times, the cycle lane is really too narrow to safely ride in. It really ought to be a minimum of 4 feet wide (allowing a 1 foot space on each side of the cyclist if they're centered in the lane. Some that I've seen aren't even as wide as the handlebars on the bike.

Where I live, a cyclist isn't required to use the cycle lane even if one is present. Do you know whether the same applies in the UK?

Re: A Type of Road Junction that Kills Cyclists

#409

Post by u801e »

jasonmaydie wrote: post #350
djsumdog wrote: post #30

Earlier quoted context omitted.

Another comment explained how the UK hates stop signs, but yes, a roundabout would be a great and very British/European solution that would probably be very effective.

I still don't understand this comment. A stop sign a simple 100$ fix to the problem but we hate stop signs so...

Why should it be necessary to always have to come to a complete stop before yielding to traffic on the intersecting roadway? A stop sign doesn't prevent one from failing to yield to traffic even after coming to a complete stop.

Re: A Type of Road Junction that Kills Cyclists

#410

Post by papermule »

brewdad wrote: post #400
papermule wrote: post #306

Earlier quoted context omitted.

Could you add some more explanation here? What is unreasonable about it?

What is the actual gain to society from requiring a cyclist license? Today, without licenses, police can and do hand out moving violations to cyclists. Today, drivers who have their license revoked or car impounded still find ways to drive cars, at least in the US. The barrier to picking up a new bike after having yours impounded by police is far lower. If it's forcing a baseline requirement for skills and knowledge,…

> What is the actual gain to society from requiring a cyclist license? Today, without licenses, police can and do hand out moving violations to cyclists.

I could, as someone who doesn't have a driving license, or has never learned to drive, go out on the road with my bicycle and more or less ride whenever and wherever I like.

I don't know what any of the road signs mean and I have no experience or training in hazard perception and collision avoidance. The law doesn't require me to. If I tried to do the same thing in a car I'd be arrested.

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