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Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

nautil.us

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Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#31

Post by c22 »

h3mb3 wrote: post #26
c22 wrote: post #8

Earlier quoted context omitted.

One of the biggest problems I experience on freeways in the US is that traveling 5 or even 10 mph above the posted speed limit makes you a "slow driver". So even though you might feel that travelling at or above the maximum legal speed limit should give you the right to occupy the "fast" lane someone will prove you wrong by screaming up your ass at 80 mph, 90 mph, or more, flashing their high beams and becoming irate…

While I think you shouldn't be a self-righteous bottleneck on the left lane, it is clear that speeding is a major factor in these highway traffic jams. It makes it impossible to keep reasonable gaps between cars as drivers always try to go as fast as possible, getting too close to the next car in the process. This always makes me go crazy when driving in the US (although this problem is probably pretty universal to a…

Yes, I experience this issue most commonly when there are two lanes and I am using cruise control. I come up behind a truck or a bus and I need to pass it, but someone is coming down the passing lane like it's their own personal express lane. If I change lanes and pass at the speed limit then the person behind me will catch up quickly and start high beaming me. The alternative is I disengage my cruise control and hang back, allowing the speeder to pass first, but this plan often backfires in denser traffic because speeders often run in packs and other cars will jump over and immediately accelerate, after letting them pass and merging behind them they will vary their speed erratically as they try to sort themselves back into the right lane (or not, some of them of them just keep barrelling down the left lane forever). Usually in this situation I'll try to compromise by accelerating to +10 over during the pass, but I am not really comfortable doing it and often it's still not enough to stop me from getting flashed at.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#32

Post by c22 »

Scea91 wrote: post #20
cryptonector wrote: post #11

Earlier quoted context omitted.

You don't get the "right" to "occupy" the left lane just because you're going fast. You have the obligation to yield the passing lane to anyone who wants to go faster. You do not know who has an emergency , and who doesn't. You don't get to enforce one law (speed limits) and flout the other (yield the passing lane). In fact, you don't get to enforce any laws if that isn't your job, and if it were your job, you should…

What is the rule exactly? 1) Yield the passing lane for anyone that wants to go faster or 2) Yield the passing lane if lane on the right is free. I am asking because I am not sure, but (2) would make more sense to me. You should not be required to break the speed limit to be allowed to pass the slower traffic.

It seems to vary by state (see the link I posted in a sibling of your comment) but the general rule is that the left lane should only be used for passing in which case logically there should only be one "pass" happening at a time so yielding is not an issue.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#33

Post by Xylakant »

alor wrote: post #30
fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

As a fellow European with experience driving in California (who prefers driving in the right-most lane), I believe it boils down to a few ways in which CA freeways are different to those in Europe: - posted speed limits fairly low (typically 65mph) - *much* higher traffic volume - traffic consisting of ~95% cars - left-lane freeway ramps - ramps usually merging directly into the freeway (mentioned by another comment…

> which requires low speed limits, which reduces throughput

Lower speed limits usually increase the density on the road which does increase the Fotoalbum throughput. It takes longer for an individual car to make a given distance, but the number of cars that pass any given point at a specific point in time is increased.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#34

Post by McDev »

LiamPa wrote: post #22
fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

In the UK this is illegal, since 2013 police can fine up to £100 and three points on your license however I don’t think it has made a blind bit of difference. Aggressively moving to the slow lane after overtaking sometimes helps..

Don't forget to give your windshield a good wash just as you're moving in front of that middle lane driver!

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#35

Post by eljefe900 »

This article doesn’t mention a strategy you can take for breaking the wave:

http://trafficwaves.org/

I originally found this info via the happy mutants at boingboing:

https://boingboing.net/2013/06/23/howto-singlehandedly-erase...

After using this technique for years, I can tell you that changing your mode of driving when you encounter traffic is difficult. Especially when you’re not used to “letting people pass”. But I’m convinced it helps break the jams.

I wonder if the autonomous vehicles in our future could adopt a similar strategy when encountering traffic to reduce jams for all of us even if they’re a small percentage of the overall drivers.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#36

Post by user5994461 »

vladvasiliu wrote: post #18
fosk wrote: post #2

In the US one of the biggest problems I have experienced is that drivers do not adhere to the international rule of having slow drivers on the right side of the freeway, especially in California. As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers. In addition t…

This is far from universal in Europe. In France, in places where highways have at least three lanes people tend to drive in the middle lane even when traffic is light. Most of the time, outside cities, merge lanes tend to be long enough even for trucks to be able to speed up enough and onramps are relatively far between so I doubt the reason people drive in the middle lane is to avoid incoming traffic. I could see ho…

There are few 3 lanes roads in France. It's mostly the highways that cross France east-west or north-south and a couple around the biggest cities.

On highways, the right most lane is occupied by trucks. You have to stay in the middle lane if you drive at the speed limit (130 km/h), otherwise you're swapping middle and right twice a minute to pass trucks.

The peripherique around Paris is saturated. All the lanes are used at all times. It's not possible to favor the right most lane.

Interesting fact. There are special rules in the french driving code for continuous stream of vehicles, for example it's prohibited to change lane unless taking a turn.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#37

Post by 40four »

eljefe900 wrote: post #35

This article doesn’t mention a strategy you can take for breaking the wave: http://trafficwaves.org/ I originally found this info via the happy mutants at boingboing: https://boingboing.net/2013/06/23/howto-singlehandedly-erase... After using this technique for years, I can tell you that changing your mode of driving when you encounter traffic is difficult. Especially when you’re not used to “letting people pass”. Bu…

I liked the article, but I agree they should have made the way to correct this more clear. They briefly mention to increase you 'headway' in the end. I wish they would have hammered this point home, instead of waxing poetically about fluid-dynamical models, & detonation waves.

The articles you linked do a great job at explaining how to fix this. Thanks for that! I believe this information should be taught as a basic part of drivers education.

I intuitively started doing this many years ago. To me, it was obvious. You can see the wave of break lights in the distance, and the wave is slowly moving back towards you. People are so impatient, they insist on riding the bumper of the car in front of them, even in a traffic jam. Then they are caught in the cycle of accelerating quickly, then coming to a full stop.

It's a simple fix. Drive slowly and steadily. Keep a large number of car lengths between the car in front of you. If you can manage to maintain the gap in front by the time you come to the back of the next 'jamiton', without breaking or stopping, the Congratulations! You just 'erased' that jam, or the wave of cars coming to a stop in that part of the jam.

All of the cars behind you will benefit. And if enough drivers were practicing this, jams would be less & clear up faster.

You are right though, the hard part is learning to not care when impatient drivers angrily speed around you, only to run up to the back of the (clearly visible) stopped cars. I just smile and laugh at how silly they are, pat myself on the back for being a smart driver, and a good citizen to all the cars behind me ;)

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#38

Post by droro »

eljefe900 wrote: post #35

This article doesn’t mention a strategy you can take for breaking the wave: http://trafficwaves.org/ I originally found this info via the happy mutants at boingboing: https://boingboing.net/2013/06/23/howto-singlehandedly-erase... After using this technique for years, I can tell you that changing your mode of driving when you encounter traffic is difficult. Especially when you’re not used to “letting people pass”. Bu…

I think it was that same article that inspired me to write an iOS app that displays your running average speed and notifies you if you deviate from it.

It's been years since I've last built and run that app, but the source is here if anyone wants to take a look: https://github.com/robinmj/DeTrafficator

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#39

Post by wreath »

eljefe900 wrote: post #35

This article doesn’t mention a strategy you can take for breaking the wave: http://trafficwaves.org/ I originally found this info via the happy mutants at boingboing: https://boingboing.net/2013/06/23/howto-singlehandedly-erase... After using this technique for years, I can tell you that changing your mode of driving when you encounter traffic is difficult. Especially when you’re not used to “letting people pass”. Bu…

> This article doesn’t mention a strategy you can take for breaking the wave: http://trafficwaves.org/

Thank you for sharing, what a pleasant read. Every time I visit my home city I'm shocked at the amount of cars in the street and consequently the traffic jam. I cannot begin to imagine how people feel after a long day at work, and what seems an even longer commute. No wonder everyone is on edge!

I think such strategies should be taught in driving schools, not only rules of the road and how to maneuver a car.

Re: Why a Traffic Flow Suddenly Turns into a Traffic Jam (2013)

#40

Post by leoedin »

There's been a big investment in the UK recently in "smart motorways"

http://www.itsinternational.com/categories/detection-monitor...

https://www.rac.co.uk/drive/advice/driving-advice/smart-moto...

These have overhead screens which show the speed limit (it's variable) and whether each lane can be used. They also have a lot of speed cameras enforcing that the displayed speed limit is being followed.

The intention is to keep traffic flowing at a much more consistent speed to avoid bunching. It also means if something happens traffic can be slowed down many miles away.

It essentially means the same road can have 30% greater capacity.

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